WO2020004461A1

WO2020004461A1 - Three-dimensional data encoding method, three-dimensional data decoding method, three-dimensional data encoding device, and three-dimensional data decoding device

Info

Publication number: WO2020004461A1
Application number: PCT/JP2019/025376
Authority: WO
Inventors: 敏康杉尾
Original assignee: パナソニックインテレクチュアルプロパティコーポレーションオブアメリカ
Priority date: 2018-06-27
Filing date: 2019-06-26
Publication date: 2020-01-02
Also published as: US20220078487A1; US11206426B2; EP3816940A4; KR20210020924A; MX2020013646A; US20210105505A1; JPWO2020004461A1; JP7322020B2; JP2024116339A; EP3816940A1; CN112313711A; JP7506231B2; CA3104630A1; MX2024010208A; BR112020024802A2; JP2023145607A

Abstract

This three-dimensional data encoding method includes: if a first flag indicates a first value (Yes at S4481), generating a first occupancy pattern that indicates the occupancy state of a plurality of second adjacent nodes including a first adjacent node, the parent node of which is different from a target node included in an N-branched tree structure (where N is an integer of 2 or greater) of a plurality of three-dimensional points included in three-dimensional data (S4482); without dividing the target node into a plurality of child nodes, determining, on the basis of the first occupancy pattern, whether first encoding that encodes a plurality of three-dimensional position information included in the target node is usable (S4483); if the first flag indicates a second value different from the first value (No at S4481), generating a second occupancy pattern that indicates the occupancy state of a plurality of third adjacent nodes not including the first adjacent node, the parent node of which is different from the target node (S4484); determining, on the basis of the second occupancy pattern, whether the first encoding is usable (S4485); and generating a bit stream that includes the first flag (S4486).

Description

Three-dimensional data encoding method, three-dimensional data decoding method, three-dimensional data encoding device, and three-dimensional data decoding device

The present disclosure relates to a three-dimensional data encoding method, a three-dimensional data decoding method, a three-dimensional data encoding device, and a three-dimensional data decoding device.

装置 In a wide range of fields, such as computer vision, map information, monitoring, infrastructure inspection, or video distribution for autonomous operation of automobiles or robots, the spread of devices or services utilizing three-dimensional data is expected in the future. The three-dimensional data is obtained by various methods such as a distance sensor such as a range finder, a stereo camera, or a combination of a plurality of monocular cameras.

One of the three-dimensional data representation methods is a representation method called a point cloud that represents the shape of a three-dimensional structure by a point group in a three-dimensional space. In the point cloud, the position and color of the point cloud are stored. Point clouds are expected to become mainstream as a method of expressing three-dimensional data, but point clouds have a very large data volume. Therefore, in the storage or transmission of three-dimensional data, it is necessary to compress the amount of data by encoding, as in the case of two-dimensional video (for example, MPEG-4 @ AVC or HEVC standardized by MPEG). Become.

{Point cloud compression} is partially supported by a public library (Point \ Cloud \ Library) that performs point cloud related processing.

技術 Further, a technology for searching for and displaying facilities located around a vehicle using three-dimensional map data is known (for example, see Patent Document 1).

International Publication No. 2014/020633

ことが It is desired that the encoding efficiency in the encoding and decoding of three-dimensional data be improved.

開示 An object of the present disclosure is to provide a three-dimensional data encoding method, a three-dimensional data decoding method, a three-dimensional data encoding device, or a three-dimensional data decoding device capable of improving encoding efficiency.

In the three-dimensional data encoding method according to an aspect of the present disclosure, when the first flag indicates the first value, an N (N is an integer of 2 or more) binary tree of a plurality of three-dimensional points included in the three-dimensional data A first occupation pattern indicating an occupancy state of a plurality of second adjacent nodes including a first adjacent node having a parent node different from the target node included in the structure is generated, and based on the first occupation pattern, a plurality of the target nodes are determined. It is determined whether or not first encoding for encoding a plurality of three-dimensional position information included in the target node can be used without dividing the child node into child nodes, and the first flag is different from the first value. When indicating the second value, a second occupation pattern indicating an occupancy state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node is generated, and based on the second occupation pattern. , Can use the first encoding It determines whether to generate a bitstream including the first flag.

The three-dimensional data decoding method according to an aspect of the present disclosure obtains a first flag from a bit stream, and when the first flag indicates a first value, sets N of a plurality of three-dimensional points included in the three-dimensional data. (N is an integer of 2 or more) A first occupation pattern indicating an occupancy state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node included in the branch tree structure is generated, and the first occupation pattern is generated. Determining whether or not first decoding for decoding a plurality of three-dimensional position information included in the target node can be used without dividing the target node into a plurality of child nodes based on the pattern; If the second node has a second value different from the first value, a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node is generated. , The second occupied pattern Based on emissions determines whether it is possible to use the first decoding.

The present disclosure can provide a three-dimensional data encoding method, a three-dimensional data decoding method, a three-dimensional data encoding device, or a three-dimensional data decoding device capable of improving encoding efficiency.

FIG. 1 is a diagram showing a configuration of encoded three-dimensional data according to the first embodiment. FIG. 2 is a diagram illustrating an example of a prediction structure between SPCs belonging to the lowest layer of the GOS according to the first embodiment. FIG. 3 is a diagram illustrating an example of a prediction structure between layers according to the first embodiment. FIG. 4 is a diagram illustrating an example of a GOS encoding order according to the first embodiment. FIG. 5 is a diagram illustrating an example of a GOS encoding order according to the first embodiment. FIG. 6 is a block diagram of the three-dimensional data encoding device according to Embodiment 1. FIG. 7 is a flowchart of the encoding process according to Embodiment 1. FIG. 8 is a block diagram of the three-dimensional data decoding device according to Embodiment 1. FIG. 9 is a flowchart of the decoding process according to Embodiment 1. FIG. 10 is a diagram showing an example of meta information according to the first embodiment. FIG. 11 is a diagram illustrating a configuration example of the SWLD according to the second embodiment. FIG. 12 is a diagram illustrating an operation example of the server and the client according to the second embodiment. FIG. 13 is a diagram illustrating an operation example of the server and the client according to the second embodiment. FIG. 14 is a diagram illustrating an operation example of the server and the client according to the second embodiment. FIG. 15 is a diagram illustrating an operation example of the server and the client according to the second embodiment. FIG. 16 is a block diagram of a three-dimensional data encoding device according to Embodiment 2. FIG. 17 is a flowchart of an encoding process according to Embodiment 2. FIG. 18 is a block diagram of a three-dimensional data decoding device according to Embodiment 2. FIG. 19 is a flowchart of a decoding process according to Embodiment 2. FIG. 20 is a diagram illustrating a configuration example of a WLD according to the second embodiment. FIG. 21 is a diagram illustrating an example of an octree structure of the WLD according to the second embodiment. FIG. 22 is a diagram illustrating a configuration example of the SWLD according to the second embodiment. FIG. 23 is a diagram illustrating an example of an octree structure of the SWLD according to the second embodiment. FIG. 24 is a block diagram of the three-dimensional data creation device according to the third embodiment. FIG. 25 is a block diagram of a three-dimensional data transmission device according to Embodiment 3. FIG. 26 is a block diagram of a three-dimensional information processing apparatus according to Embodiment 4. FIG. 27 is a block diagram of the three-dimensional data creation device according to the fifth embodiment. FIG. 28 is a diagram illustrating a configuration of a system according to the sixth embodiment. FIG. 29 is a block diagram of a client device according to Embodiment 6. FIG. 30 is a block diagram of a server according to Embodiment 6. FIG. 31 is a flowchart of a three-dimensional data creation process by the client device according to the sixth embodiment. FIG. 32 is a flowchart of sensor information transmission processing by the client device according to the sixth embodiment. FIG. 33 is a flowchart of three-dimensional data creation processing by the server according to Embodiment 6. FIG. 34 is a flowchart of a three-dimensional map transmission process by the server according to Embodiment 6. FIG. 35 is a diagram showing a configuration of a modification of the system according to Embodiment 6. FIG. 36 is a diagram showing a configuration of a server and a client device according to Embodiment 6. FIG. 37 is a block diagram of a three-dimensional data encoding device according to Embodiment 7. FIG. 38 is a diagram illustrating an example of a prediction residual according to Embodiment 7. FIG. 39 is a diagram illustrating an example of a volume according to the seventh embodiment. FIG. 40 is a diagram illustrating an example of an octree representation of a volume according to the seventh embodiment. FIG. 41 is a diagram illustrating an example of a bit string of a volume according to the seventh embodiment. FIG. 42 is a diagram illustrating an example of an octree representation of a volume according to the seventh embodiment. FIG. 43 is a diagram illustrating an example of a volume according to the seventh embodiment. FIG. 44 is a diagram for describing intra prediction processing according to Embodiment 7. FIG. 45 is a diagram for explaining rotation and translation processing according to the seventh embodiment. FIG. 46 is a diagram illustrating a syntax example of an RT application flag and RT information according to the seventh embodiment. FIG. 47 is a diagram for explaining the inter prediction processing according to the seventh embodiment. FIG. 48 is a block diagram of a three-dimensional data decoding device according to Embodiment 7. FIG. 49 is a flowchart of a three-dimensional data encoding process performed by the three-dimensional data encoding device according to Embodiment 7. FIG. 50 is a flowchart of a three-dimensional data decoding process by the three-dimensional data decoding device according to the seventh embodiment. FIG. 51 is a diagram illustrating a reference relationship in the octree structure according to the eighth embodiment. FIG. 52 is a diagram showing a reference relationship in a spatial domain according to the eighth embodiment. FIG. 53 is a diagram illustrating an example of an adjacent reference node according to the eighth embodiment. FIG. 54 is a diagram illustrating a relationship between a parent node and a node according to the eighth embodiment. FIG. 55 is a diagram illustrating an example of an occupancy code of a parent node according to Embodiment 8. FIG. 56 is a block diagram of a three-dimensional data encoding device according to Embodiment 8. FIG. 57 is a block diagram of a three-dimensional data decoding device according to Embodiment 8. FIG. 58 is a flowchart of a three-dimensional data encoding process according to Embodiment 8. FIG. 59 is a flowchart of a three-dimensional data decoding process according to Embodiment 8. FIG. 60 is a diagram illustrating an example of switching of the encoding tables according to Embodiment 8. FIG. 61 is a diagram illustrating a reference relationship in a spatial region according to the first modification of the eighth embodiment. FIG. 62 is a diagram illustrating a syntax example of header information according to Modification Example 1 of Embodiment 8. FIG. 63 is a diagram illustrating a syntax example of header information according to Modification Example 1 of Embodiment 8. FIG. 64 is a diagram illustrating an example of an adjacent reference node according to the second modification of the eighth embodiment. FIG. 65 is a diagram illustrating an example of a target node and an adjacent node according to Modification 2 of Embodiment 8. FIG. 66 is a diagram illustrating a reference relationship in the octree structure according to the third modification of the eighth embodiment. FIG. 67 is a diagram illustrating a reference relationship in a spatial region according to the third modification of the eighth embodiment. FIG. 68 is a diagram illustrating an example and processing of an adjacent node according to Embodiment 9. FIG. 69 is a flowchart of a three-dimensional data encoding process according to Embodiment 9. FIG. 70 is a flowchart of a three-dimensional data encoding process according to Embodiment 9. FIG. 71 is a flowchart of a modification of the three-dimensional data encoding process according to Embodiment 9. FIG. 72 is a flowchart of a three-dimensional data decoding process according to Embodiment 9. FIG. 73 is a flowchart of a modification of the three-dimensional data decoding process according to Embodiment 9. FIG. 74 is a diagram illustrating a syntax example of a header according to the ninth embodiment. FIG. 75 is a diagram illustrating a syntax example of node information according to the ninth embodiment. FIG. 76 is a block diagram of a three-dimensional data encoding device according to Embodiment 9. FIG. 77 is a block diagram of a three-dimensional data decoding device according to Embodiment 9. FIG. 78 is a flowchart of a modification of the three-dimensional data encoding process according to Embodiment 9. FIG. 79 is a flowchart of a modification of the three-dimensional data encoding process according to Embodiment 9. FIG. 80 is a flowchart of a modification of the three-dimensional data decoding process according to Embodiment 9. FIG. 81 is a flowchart of a modification of the three-dimensional data decoding process according to Embodiment 9. FIG. 82 is a flowchart of a three-dimensional data encoding process according to Embodiment 9. FIG. 83 is a flowchart of a three-dimensional data decoding process according to Embodiment 9.

According to this, the three-dimensional data encoding method can switch the occupation pattern of the adjacent node used to determine whether the first encoding is available or not in accordance with the first flag. This makes it possible to appropriately determine whether the first encoding can be used, thereby improving the encoding efficiency.

For example, when it is determined that the first encoding can be used, it is determined whether to use the first encoding based on a predetermined condition, and when it is determined that the first encoding is used, If the target node is encoded using one encoding and it is determined not to use the first encoding, the target node is encoded using a second encoding that divides the target node into a plurality of child nodes. , The bit stream may further include a second flag indicating whether to use the first encoding.

For example, in the determination as to whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, the first encoding pattern or the second occupation pattern is included in the parent node. Whether or not the first encoding can be used may be determined based on the number of occupied nodes.

For example, based on the first occupation pattern or the second occupation pattern, in the determination as to whether the first encoding can be used, the first occupation pattern or the second occupation pattern and a grandfather node of the target node are determined. May be determined based on the number of occupied nodes included in the first encoding.

For example, based on the first occupation pattern or the second occupation pattern, in determining whether the first encoding can be used, the first occupation pattern or the second occupation pattern and the hierarchy to which the target node belongs Based on the above, it may be determined whether or not the first encoding can be used.

According to this, the three-dimensional data decoding method can switch the occupation pattern of the adjacent node used to determine whether the first encoding can be used or not in accordance with the first flag. This makes it possible to appropriately determine whether the first encoding can be used, thereby improving the encoding efficiency.

For example, when it is determined that the first decoding can be used, a second flag indicating whether to use the first decoding is obtained from the bit stream, and the first decoding is used based on the second flag. If so, a second decoding that divides the target node into a plurality of child nodes by decoding the target node using the first decoding and not using the first decoding by the second flag May be used to decode the target node.

For example, based on the first occupation pattern or the second occupation pattern, in the determination as to whether the first decoding can be used, the first occupation pattern or the second occupation pattern and the occupation included in the parent node are determined. Whether or not the first decoding can be used may be determined based on the number of nodes in the state.

For example, based on the first occupation pattern or the second occupation pattern, in determining whether the first decoding can be used, the first occupation pattern or the second occupation pattern and the grandfather node of the target node Whether or not the first decoding can be used may be determined based on the number of occupied nodes included.

For example, based on the first occupation pattern or the second occupation pattern, in the determination as to whether the first decoding can be used, the first occupation pattern or the second occupation pattern and the hierarchy to which the target node belongs It may be determined whether or not the first decryption can be used based on.

Further, a three-dimensional data encoding device according to an aspect of the present disclosure is a three-dimensional data encoding device that encodes a plurality of three-dimensional points having attribute information, the processor including a processor, a memory, and the processor When the first flag indicates a first value using the memory, a target node included in an N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data is Generating a first occupation pattern indicating an occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node, without dividing the target node into a plurality of child nodes based on the first occupation pattern; It is determined whether or not first encoding for encoding a plurality of three-dimensional position information included in the target node is available, and the first flag indicates a second value different from the first value The parent node differs from the target node. Generating a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node, and determining whether or not the first encoding can be used based on the second occupation pattern. , Generating a bit stream including the first flag.

According to this, the three-dimensional data encoding device can switch the occupation pattern of the adjacent node used to determine whether the first encoding is available or not in accordance with the first flag. This makes it possible to appropriately determine whether the first encoding can be used, thereby improving the encoding efficiency.

Further, a three-dimensional data decoding device according to an aspect of the present disclosure is a three-dimensional data decoding device that decodes a plurality of three-dimensional points having attribute information, including a processor and a memory, wherein the processor is When the first flag indicates a first value using a memory, a target node and a parent node included in an N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data Generates a first occupation pattern indicating an occupation state of a plurality of second adjacent nodes including first adjacent nodes different from each other, and does not divide the target node into a plurality of child nodes based on the first occupation pattern. It is determined whether or not first decoding for decoding a plurality of pieces of three-dimensional position information included in a node can be used, and when the first flag indicates a second value different from the first value, the target node Before parent node is different Generating a second occupancy pattern showing a plurality of occupancy of the third adjacent node that does not include the first adjacent node, on the basis of the second occupation pattern, determines whether or not it is possible to use the first decoding.

According to this, the three-dimensional data decoding device can switch the occupation pattern of the adjacent node used to determine whether the first encoding can be used according to the first flag. This makes it possible to appropriately determine whether the first encoding can be used, thereby improving the encoding efficiency.

Note that these comprehensive or specific aspects may be realized by a recording medium such as a system, a method, an integrated circuit, a computer program or a computer-readable CD-ROM, and the system, the method, the integrated circuit, and the computer program. And any combination of recording media.

Hereinafter, embodiments will be specifically described with reference to the drawings. Each of the embodiments described below shows a specific example of the present disclosure. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, steps, order of steps, and the like shown in the following embodiments are merely examples, and do not limit the present disclosure. Further, among the components in the following embodiments, components not described in the independent claims indicating the highest concept are described as arbitrary components.

(Embodiment 1)
First, a data structure of encoded three-dimensional data (hereinafter, also referred to as encoded data) according to the present embodiment will be described. FIG. 1 is a diagram showing a configuration of encoded three-dimensional data according to the present embodiment.

In the present embodiment, the three-dimensional space is divided into spaces (SPCs) corresponding to pictures in encoding moving images, and three-dimensional data is encoded in units of spaces. The space is further divided into volumes (VLM) corresponding to macroblocks and the like in video coding, and prediction and conversion are performed in units of VLM. The volume includes a plurality of voxels (VXL), which are the minimum units associated with the position coordinates. Note that the prediction refers to another processing unit, generates prediction three-dimensional data similar to the processing unit to be processed, and generates the prediction three-dimensional data and the processing target to be processed, similarly to the prediction performed on the two-dimensional image. This is to encode the difference from the processing unit. This prediction includes not only spatial prediction referring to another prediction unit at the same time but also temporal prediction referring to a prediction unit at a different time.

For example, when encoding a three-dimensional space represented by point cloud data such as a point cloud, a three-dimensional data encoding device (hereinafter, also referred to as an encoding device) sets a point cloud according to a voxel size. , Or a plurality of points included in the voxel are collectively encoded. If the voxels are subdivided, the three-dimensional shape of the point group can be expressed with high precision, and if the voxel size is increased, the three-dimensional shape of the point group can be roughly expressed.

In the following, the case where the three-dimensional data is a point cloud will be described as an example, but the three-dimensional data is not limited to the point cloud, and may be any form of three-dimensional data.

Alternatively, voxels having a hierarchical structure may be used. In this case, in the n-th layer, whether or not the sample points exist in the (n-1) -th or lower layer (the lower layer of the n-th layer) may be indicated in order. For example, when decoding only the n-th layer, if there are sample points in the (n−1) -th and lower layers, decoding can be performed assuming that the sample point exists at the center of the voxel in the n-th layer.

{Circle around (4)} The encoding device acquires the point cloud data using a distance sensor, a stereo camera, a monocular camera, a gyro, an inertial sensor, or the like.

The space can be an intra space (I-SPC) that can be decoded independently, a predictive space (P-SPC) that can only be referenced in one direction, and a bidirectional reference, as in the case of video encoding. Classified into any of at least three prediction structures including a bidirectional space (B-SPC). The space has two types of time information, that is, a decoding time and a display time.

As shown in FIG. 1, as a processing unit including a plurality of spaces, a random access unit, GOS (Group Of Space), exists. Further, there is a world (WLD) as a processing unit including a plurality of GOSs.

The space area occupied by the world is associated with the absolute position on the earth by GPS or latitude and longitude information. This position information is stored as meta information. Note that the meta information may be included in the encoded data, or may be transmitted separately from the encoded data.

In the GOS, all SPCs may be three-dimensionally adjacent to each other, or some SPCs may not be three-dimensionally adjacent to other SPCs.

In the following, processing such as encoding, decoding, or reference to three-dimensional data included in a processing unit such as GOS, SPC, or VLM is also simply referred to as encoding, decoding, or referencing a processing unit. The three-dimensional data included in the processing unit includes, for example, at least one set of a spatial position such as three-dimensional coordinates and a characteristic value such as color information.

Next, the prediction structure of the SPC in the GOS will be described. A plurality of SPCs in the same GOS or a plurality of VLMs in the same SPC occupy different spaces, but have the same time information (decoding time and display time).

Ｓ Also, the first SPC in the decoding order in the GOS is the I-SPC. Also, there are two types of GOS, closed GOS and open GOS. The closed GOS is a GOS that can decode all SPCs in the GOS when starting decoding from the first I-SPC. In the open GOS, some SPCs whose display time is earlier than the head I-SPC in the GOS refer to different GOSs, and cannot be decrypted only by the GOS.

In the case of encoded data such as map information, the WLD may be decoded in a direction opposite to the encoding order, and it is difficult to reproduce in the backward direction if there is a dependency between GOSs. Therefore, in such a case, the closed GOS is basically used.

GOS has a layer structure in the height direction, and encoding or decoding is performed sequentially from the SPC of the lower layer.

FIG. 2 is a diagram showing an example of a prediction structure between SPCs belonging to the lowest layer of the GOS. FIG. 3 is a diagram illustrating an example of a prediction structure between layers.

One or more I-SPCs exist in GOS. Objects such as humans, animals, cars, bicycles, signals, and buildings serving as landmarks exist in the three-dimensional space, and it is effective to encode small-sized objects as I-SPC. For example, a three-dimensional data decoding device (hereinafter also referred to as a decoding device) decodes only the I-SPC in the GOS when decoding the GOS with a low processing amount or at a high speed.

The encoding device may switch the encoding interval or the appearance frequency of the I-SPC according to the density of the object in the WLD.

In addition, in the configuration illustrated in FIG. 3, the encoding device or the decoding device sequentially encodes or decodes a plurality of layers from a lower layer (layer 1). Thus, for example, the priority of data near the ground, which has more information for an autonomous vehicle, can be increased.

In the coded data used in a drone or the like, the coded data may be coded or decoded in the GOS in order from the SPC of the upper layer in the height direction.

The encoding device or the decoding device may encode or decode a plurality of layers so that the decoding device can roughly understand the GOS and gradually increase the resolution. For example, the encoding device or the decoding device may perform encoding or decoding in the order of

layers

3, 8, 1, 9,.

Next, how to handle static and dynamic objects will be described.

In the three-dimensional space, there are static objects or scenes such as buildings or roads (hereinafter collectively referred to as static objects) and dynamic objects such as cars or people (hereinafter referred to as dynamic objects). I do. Object detection is separately performed by extracting feature points from point cloud data, camera images from a stereo camera or the like, and the like. Here, an example of a dynamic object encoding method will be described.

The first method is a method of encoding a static object and a dynamic object without distinction. The second method is a method for distinguishing between a static object and a dynamic object by identification information.

For example, GOS is used as an identification unit. In this case, the GOS including the SPC configuring the static object and the GOS including the SPC configuring the dynamic object are distinguished by the identification information stored in the encoded data or separately from the encoded data.

Alternatively, SPC may be used as the identification unit. In this case, the SPC including the VLM forming the static object and the SPC including the VLM forming the dynamic object are distinguished by the identification information.

Alternatively, VLM or VXL may be used as the identification unit. In this case, the VLM or VXL including the static object is distinguished from the VLM or VXL including the dynamic object by the identification information.

The encoding device may encode the dynamic object as one or more VLMs or SPCs, and encode the VLM or SPC including the static object and the SPC including the dynamic object as different GOSs. In addition, when the size of the GOS is variable according to the size of the dynamic object, the encoding device separately stores the size of the GOS as meta information.

The encoding device may encode the static object and the dynamic object independently of each other, and superimpose the dynamic object on a world composed of the static objects. At this time, the dynamic object is constituted by one or more SPCs, and each SPC is associated with one or more SPCs constituting a static object on which the SPC is superimposed. The dynamic object may be represented by one or more VLMs or VXLs instead of the SPC.

The encoding device may encode the static object and the dynamic object as different streams from each other.

The encoding device may generate a GOS including one or more SPCs constituting a dynamic object. Further, the encoding device may set the GOS (GOS_M) including the dynamic object and the GOS of the static object corresponding to the space area of the GOS_M to the same size (occupy the same space area). Thereby, the superimposition process can be performed in GOS units.

The P-SPC or the B-SPC constituting the dynamic object may refer to an SPC included in a different encoded GOS. In the case where the position of the dynamic object changes over time and the same dynamic object is encoded as GOS at different times, reference across GOS is effective from the viewpoint of the compression ratio.

{Circle around (1)} The first method and the second method may be switched according to the use of the encoded data. For example, when using encoded three-dimensional data as a map, it is desirable to be able to separate dynamic objects, so the encoding device uses the second method. On the other hand, when encoding three-dimensional data of an event such as a concert or a sport, the encoding device uses the first method unless it is necessary to separate dynamic objects.

復号 The decoding time and display time of GOS or SPC can be stored in the encoded data or as meta information. In addition, the time information of all static objects may be the same. At this time, the actual decoding time and display time may be determined by the decoding device. Alternatively, different values may be assigned to the GOS or SPC as the decoding time, and the same value may be assigned to all the display times. Furthermore, the decoder has a buffer of a predetermined size, such as a decoder model in video coding such as HEVC (Hydrophetic Reference Decoder), and can decode without fail if a bit stream is read at a predetermined bit rate according to a decoding time. May be introduced.

Next, the arrangement of GOS in the world will be described. The coordinates of the three-dimensional space in the world are represented by three coordinate axes (x-axis, y-axis, z-axis) orthogonal to each other. By providing a predetermined rule in the order of GOS encoding, encoding can be performed so that spatially adjacent GOSs are continuous in encoded data. For example, in the example shown in FIG. 4, GOS in the xz plane is continuously encoded. After the encoding of all GOS in a certain xz plane is completed, the value of the y-axis is updated. That is, as the encoding progresses, the world extends in the y-axis direction. The GOS index numbers are set in the order of encoding.

Here, the three-dimensional space of the world is associated one-to-one with GPS or geographical absolute coordinates such as latitude and longitude. Alternatively, a three-dimensional space may be represented by a relative position from a preset reference position. The directions of the x-axis, y-axis, and z-axis in the three-dimensional space are expressed as direction vectors determined based on latitude, longitude, and the like, and the direction vectors are stored as meta information together with the encoded data.

Also, the size of the GOS is fixed, and the encoding device stores the size as meta information. Further, the size of the GOS may be switched according to, for example, whether or not it is in an urban area or indoors or outdoors. That is, the size of the GOS may be switched according to the amount or properties of an object having information value. Alternatively, the encoding device may adaptively switch the size of the GOS or the interval between I-SPCs in the GOS according to the density of the objects and the like in the same world. For example, the encoding device reduces the size of the GOS and shortens the interval between I-SPCs in the GOS as the density of the objects increases.

In the example of FIG. 5, since the object density is high in the third to tenth GOS areas, the GOS is subdivided in order to realize random access with fine granularity. The seventh to tenth GOSs are located behind the third to sixth GOSs, respectively.

Next, the configuration and operation flow of the three-dimensional data encoding device according to the present embodiment will be described. FIG. 6 is a block diagram of three-dimensional data encoding device 100 according to the present embodiment. FIG. 7 is a flowchart illustrating an operation example of the three-dimensional data encoding device 100.

The three-dimensional data encoding device 100 illustrated in FIG. 6 generates the encoded three-dimensional data 112 by encoding the three-dimensional data 111. The three-dimensional data encoding device 100 includes an acquisition unit 101, an encoding area determination unit 102, a division unit 103, and an encoding unit 104.

As shown in FIG. 7, first, the acquiring unit 101 acquires the three-dimensional data 111 that is point cloud data (S101).

Next, the encoding area determination unit 102 determines an encoding target area from among the spatial areas corresponding to the acquired point cloud data (S102). For example, the coding area determination unit 102 determines a spatial area around the position as a coding target area according to the position of the user or the vehicle.

Next, the dividing unit 103 divides the point cloud data included in the encoding target area into processing units. Here, the processing unit is the above-described GOS, SPC, or the like. The region to be coded corresponds to, for example, the world described above. Specifically, the dividing unit 103 divides the point cloud data into processing units based on a predetermined GOS size or the presence or absence or size of a dynamic object (S103). Further, the dividing unit 103 determines the start position of the SPC which is the first in the coding order in each GOS.

Next, the encoding unit 104 generates encoded three-dimensional data 112 by sequentially encoding a plurality of SPCs in each GOS (S104).

Here, an example has been described in which the encoding target area is divided into GOS and SPC, and then each GOS is encoded, but the processing procedure is not limited to the above. For example, a procedure may be used in which the configuration of one GOS is determined, then the GOS is encoded, and then the configuration of the next GOS is determined.

三 Thus, the three-dimensional data encoding device 100 generates the encoded three-dimensional data 112 by encoding the three-dimensional data 111. Specifically, the three-dimensional data encoding device 100 divides the three-dimensional data into random access units, each of which is associated with a three-dimensional coordinate, and is divided into first processing units (GOS). The processing unit (GOS) is divided into a plurality of second processing units (SPC), and the second processing unit (SPC) is divided into a plurality of third processing units (VLM). Further, the third processing unit (VLM) includes one or more voxels (VXL), which are minimum units to be associated with position information.

Next, the three-dimensional data encoding device 100 generates encoded three-dimensional data 112 by encoding each of the plurality of first processing units (GOS). Specifically, the three-dimensional data encoding device 100 encodes each of the plurality of second processing units (SPC) in each first processing unit (GOS). Further, the three-dimensional data encoding device 100 encodes each of the plurality of third processing units (VLMs) in each second processing unit (SPC).

For example, when the first processing unit (GOS) to be processed is a closed GOS, the three-dimensional data encoding apparatus 100 may use the second processing unit to be processed included in the first processing unit (GOS) to be processed. (SPC) is encoded with reference to another second processing unit (SPC) included in the first processing unit (GOS) to be processed. That is, the three-dimensional data encoding device 100 does not refer to the second processing unit (SPC) included in the first processing unit (GOS) different from the first processing unit (GOS) to be processed.

On the other hand, if the first processing unit (GOS) to be processed is an open GOS, the second processing unit (SPC) to be processed included in the first processing unit (GOS) to be processed is replaced with the second processing unit (SPC) to be processed. Another second processing unit (SPC) included in one processing unit (GOS) or a second processing unit (SPC) included in a first processing unit (GOS) different from the first processing unit (GOS) to be processed ) And perform encoding.

In addition, the three-dimensional data encoding apparatus 100 may use the first type (I-SPC) that does not refer to another second processing unit (SPC) as the type of the second processing unit (SPC) to be processed, One of a second type (P-SPC) referring to the second processing unit (SPC) and a third type referring to the other two second processing units (SPC) is selected, and processing is performed according to the selected type. The target second processing unit (SPC) is encoded.

Next, the configuration and operation flow of the three-dimensional data decoding device according to the present embodiment will be described. FIG. 8 is a block diagram of a block of three-dimensional data decoding device 200 according to the present embodiment. FIG. 9 is a flowchart illustrating an operation example of the three-dimensional data decoding device 200.

三 The three-dimensional data decoding device 200 illustrated in FIG. 8 generates the decoded three-dimensional data 212 by decoding the encoded three-dimensional data 211. Here, the encoded three-dimensional data 211 is, for example, the encoded three-dimensional data 112 generated by the three-dimensional data encoding device 100. The three-dimensional data decoding device 200 includes an acquisition unit 201, a decoding start GOS determining unit 202, a decoding SPC determining unit 203, and a decoding unit 204.

First, the acquiring unit 201 acquires the encoded three-dimensional data 211 (S201). Next, the decryption start GOS determination unit 202 determines the GOS to be decrypted (S202). Specifically, the decoding start GOS determining unit 202 refers to the meta information stored in the encoded three-dimensional data 211 or separately from the encoded three-dimensional data, and determines a spatial position, an object, or an object to start decoding. , The GOS including the SPC corresponding to the time is determined as the GOS to be decoded.

Next, the decoding SPC determining unit 203 determines the type (I, P, B) of the SPC to be decoded in the GOS (S203). For example, the decoding SPC determining unit 203 determines whether to (1) decode only I-SPC, (2) decode I-SPC and P-SPC, or (3) decode all types. If the type of SPC to be decoded is determined in advance, such as decoding all SPCs, this step may not be performed.

Next, the decoding unit 204 obtains an address position at which the first SPC in the decoding order (same as the encoding order) in the GOS starts in the encoded three-dimensional data 211, and obtains a code of the first SPC from the address position. The encrypted data is acquired, and each SPC is sequentially decoded from the leading SPC (S204). Note that the address position is stored in meta information or the like.

三 Thus, the three-dimensional data decoding device 200 decodes the decoded three-dimensional data 212. Specifically, the three-dimensional data decoding device 200 decodes each of the encoded three-dimensional data 211 of the first processing unit (GOS), which is a random access unit and is associated with a three-dimensional coordinate. Thereby, the decoded three-dimensional data 212 of the first processing unit (GOS) is generated. More specifically, the three-dimensional data decoding device 200 decodes each of the plurality of second processing units (SPC) in each first processing unit (GOS). Further, the three-dimensional data decoding device 200 decodes each of the plurality of third processing units (VLM) in each second processing unit (SPC).

Hereinafter, the meta information for random access will be described. This meta information is generated by the three-dimensional data encoding device 100 and is included in the encoded three-dimensional data 112 (211).

In the conventional random access in a two-dimensional moving image, decoding is started from the first frame of a random access unit near a specified time. On the other hand, in the world, random access to space (coordinates or objects) is assumed in addition to time.

Therefore, in order to realize random access to at least the three elements of coordinates, objects, and time, a table is prepared that associates each element with the GOS index number. Further, the GOS index number is associated with the address of the I-SPC at the head of the GOS. FIG. 10 is a diagram illustrating an example of a table included in the meta information. Note that not all the tables shown in FIG. 10 need to be used, and at least one table may be used.

Hereinafter, random access starting from coordinates will be described as an example. When accessing the coordinates (x2, y2, z2), first, referring to the coordinate-GOS table, it can be seen that the point whose coordinates are (x2, y2, z2) is included in the second GOS. Next, by referring to the GOS address table, it is found that the address of the first I-SPC in the second GOS is addr (2), so the decoding unit 204 obtains data from this address and starts decoding. I do.

The address may be an address in a logical format or a physical address of an HDD or a memory. Further, information for specifying the file segment may be used instead of the address. For example, a file segment is a unit obtained by segmenting one or more GOSs.

If the object spans a plurality of GOS, the object-GOS table may indicate a plurality of GOS to which the object belongs. If the plurality of GOSs are closed GOSs, the encoding device and the decoding device can perform encoding or decoding in parallel. On the other hand, if the plurality of GOSs are open GOSs, the plurality of GOSs can refer to each other to increase the compression efficiency.

Examples of objects include humans, animals, cars, bicycles, traffic lights, and landmark buildings. For example, the three-dimensional data encoding device 100 extracts characteristic points specific to an object from a three-dimensional point cloud or the like when encoding a world, detects an object based on the characteristic point, and assigns the detected object to a random access point. Can be set as

As described above, the three-dimensional data encoding device 100 includes the first information indicating the plurality of first processing units (GOS) and the three-dimensional coordinates associated with each of the plurality of first processing units (GOS). Generate Also, the encoded three-dimensional data 112 (211) includes this first information. Further, the first information further indicates at least one of an object, a time, and a data storage destination associated with each of the plurality of first processing units (GOS).

The three-dimensional data decoding device 200 acquires the first information from the encoded three-dimensional data 211, and uses the first information to encode the three-dimensional data of the first processing unit corresponding to the specified three-dimensional coordinate, object, or time. The original data 211 is specified, and the encoded three-dimensional data 211 is decoded.

Hereinafter, other examples of the meta information will be described. In addition to the random access meta information, the three-dimensional data encoding device 100 may generate and store the following meta information. Further, the three-dimensional data decoding device 200 may use this meta information at the time of decoding.

(4) In the case where three-dimensional data is used as map information, a profile is defined according to the application, and information indicating the profile may be included in the meta information. For example, a profile for an urban area or a suburb or a flying object is defined, and the maximum or minimum size of the world, SPC or VLM is defined in each of the profiles. For example, the minimum size of the VLM is set smaller for urban areas because more detailed information is required than for suburban areas.

The meta information may include a tag value indicating the type of the object. This tag value is associated with the VLM, SPC, or GOS that makes up the object. For example, a tag value “0” indicates “person”, a tag value “1” indicates “car”, a tag value “2” indicates “traffic light”, and so on. Is also good. Alternatively, if the type of the object is difficult to determine or need not be determined, a tag value indicating the size or a property such as a dynamic object or a static object may be used.

(4) The meta information may include information indicating a range of a space area occupied by the world.

The meta information may store the size of the SPC or VXL as header information common to a plurality of SPCs such as an entire stream of encoded data or SPCs in the GOS.

The meta information may include identification information of a distance sensor or a camera used for generating the point cloud, or information indicating the positional accuracy of a point cloud in the point cloud.

The meta information may include information indicating whether the world is composed of only static objects or includes dynamic objects.

Hereinafter, a modified example of the present embodiment will be described.

The encoding device or the decoding device may encode or decode two or more different SPCs or GOSs in parallel. The GOS to be encoded or decoded in parallel can be determined based on meta information indicating the spatial position of the GOS.

In the case where the three-dimensional data is used as a space map when a car or a flying object moves, or a case where such a space map is generated, the encoding device or the decoding device uses the GPS, the route information, the zoom magnification, or the like. GOS or SPC included in the space specified based on the information may be encoded or decoded.

復号 Also, the decoding device may perform decoding sequentially from a space close to the self-position or the travel route. The encoding device or the decoding device may encode or decode a space farther from the self-position or the travel route with a lower priority than a space close thereto. Here, lowering the priority means lowering the processing order, lowering the resolution (processing by thinning out), or lowering the image quality (improving the coding efficiency, for example, increasing the quantization step). .

復号 Further, when decoding the encoded data hierarchically encoded in the space, the decoding device may decode only the lower layer.

The decoding device may preferentially decode from the lower hierarchy according to the zoom factor or the application of the map.

Further, in applications such as self-position estimation or object recognition performed during autonomous traveling of a car or a robot, an encoding device or a decoding device reduces a resolution except for an area within a specific height from a road surface (an area for recognition). Or decryption may be performed.

The encoding device may individually encode the point clouds representing the spatial shapes of the indoor space and the outdoor space. For example, by separating GOS representing an indoor room (indoor GOS) and GOS representing an outdoor room (outdoor GOS), the decoding device selects a GOS to be decoded according to the viewpoint position when using encoded data. it can.

The encoding device may encode the indoor GOS and the outdoor GOS whose coordinates are close to each other so as to be adjacent in the encoded stream. For example, the encoding device associates both identifiers and stores information indicating the associated identifier in the encoded stream or separately stored meta information. Thereby, the decoding device can identify the indoor GOS and the outdoor GOS whose coordinates are close by referring to the information in the meta information.

The encoding device may switch the size of the GOS or the SPC between the indoor GOS and the outdoor GOS. For example, the encoding device sets the size of the GOS smaller indoors than when outdoors. In addition, the encoding device may change the accuracy at the time of extracting a feature point from a point cloud or the accuracy of object detection between the indoor GOS and the outdoor GOS.

The encoding device may add, to the encoded data, information for the decoding device to display the dynamic object separately from the static object. Thus, the decoding device can display the dynamic object together with the red frame or the explanatory characters. Note that the decoding device may display only a red frame or an explanatory character instead of the dynamic object. Further, the decoding device may display a more detailed object type. For example, a red frame may be used for a car and a yellow frame may be used for a person.

Further, the encoding device or the decoding device encodes the dynamic object and the static object as different SPCs or GOSs according to the appearance frequency of the dynamic object or the ratio between the static object and the dynamic object. Alternatively, it may be determined whether or not to decrypt. For example, when the appearance frequency or ratio of the dynamic object exceeds the threshold, SPC or GOS in which the dynamic object and the static object are mixed is allowed, and the appearance frequency or ratio of the dynamic object does not exceed the threshold. Does not allow SPC or GOS in which dynamic objects and static objects coexist.

When detecting a dynamic object not from a point cloud but from two-dimensional image information of a camera, the encoding device separately obtains information (a frame or a character) for identifying a detection result and an object position, These pieces of information may be encoded as part of three-dimensional encoded data. In this case, the decoding device superimposes and displays auxiliary information (frame or character) indicating the dynamic object on the decoding result of the static object.

The encoding device may change the density of the VXL or VLM in the SPC according to the complexity of the shape of the static object. For example, the encoding device sets VXL or VLM densely as the shape of the static object becomes more complicated. Furthermore, the encoding device may determine a quantization step or the like when quantizing the spatial position or the color information according to the density of the VXL or VLM. For example, the encoding device sets a smaller quantization step as VXL or VLM becomes denser.

As described above, the encoding device or the decoding device according to the present embodiment encodes or decodes a space in units of space having coordinate information.

(4) The encoding device and the decoding device perform encoding or decoding on a volume basis in the space. The volume includes a voxel that is the minimum unit associated with the position information.

In addition, the encoding device and the decoding device associate arbitrary elements with a table in which each element of spatial information including coordinates, objects, time, and the like is associated with a GOP, or a table in which each element is associated. Encoding or decoding. Further, the decoding device determines coordinates using the value of the selected element, specifies a volume, a voxel or a space from the coordinates, and decodes a space including the volume or the voxel or the specified space.

The encoding device determines a volume, a voxel, or a space that can be selected by an element by extracting feature points or recognizing an object, and encodes the volume, the voxel, or the space that can be randomly accessed.

The space refers to an I-SPC that can be encoded or decoded by itself, a P-SPC encoded or decoded with reference to any one processed space, and any two processed spaces. And B-SPC to be coded or decoded.

# One or more volumes correspond to static or dynamic objects. The space including the static object and the space including the dynamic object are encoded or decoded as different GOSs. That is, the SPC including the static object and the SPC including the dynamic object are assigned to different GOSs.

Dynamic objects are encoded or decoded on an object-by-object basis and are associated with one or more spaces containing static objects. That is, the plurality of dynamic objects are individually encoded, and the encoded data of the obtained plurality of dynamic objects is associated with the SPC including the static object.

The encoding device and the decoding device perform encoding or decoding by increasing the priority of the I-SPC in the GOS. For example, the encoding device performs encoding so that deterioration of I-SPC is reduced (so that the original three-dimensional data is more faithfully reproduced after decoding). The decoding device decodes, for example, only I-SPC.

The encoding device may perform encoding by changing the frequency of using I-SPC according to the density or the number (amount) of objects in the world. That is, the encoding device changes the frequency of selecting the I-SPC according to the number or coarseness of the objects included in the three-dimensional data. For example, the encoding device uses the I space more frequently as the objects in the world are denser.

(4) The encoding device sets a random access point in GOS units and stores information indicating a spatial area corresponding to GOS in the header information.

The encoding device uses, for example, a default value as the space size of the GOS. Note that the encoding device may change the size of the GOS according to the number (amount) or coarseness of the objects or dynamic objects. For example, the encoding device reduces the space size of the GOS as the number of objects or dynamic objects increases or the number of dynamic objects increases.

(4) The space or volume includes a feature point group derived using information obtained by a sensor such as a depth sensor, a gyro, or a camera. The coordinates of the feature point are set at the center position of the voxel. Further, it is possible to realize high-accuracy position information by subdividing voxels.

The feature point group is derived using a plurality of pictures. The plurality of pictures have at least two types of time information: actual time information and the same time information (for example, an encoded time used for rate control or the like) in the plurality of pictures associated with the space.

(4) Encoding or decoding is performed in GOS units including one or more spaces.

The encoding device and the decoding device predict the P space or the B space in the GOS to be processed with reference to the space in the processed GOS.

Alternatively, the encoding device and the decoding device predict the P space or the B space in the GOS to be processed using the processed space in the GOS to be processed without referring to different GOSs.

The encoding device and the decoding device transmit or receive an encoded stream in world units including one or more GOSs.

GOS has a layer structure in at least one direction in the world, and the encoding device and the decoding device perform encoding or decoding from the lower layer. For example, a randomly accessible GOS belongs to the lowest layer. GOS belonging to the upper layer refers to GOS belonging to the same layer or lower. That is, the GOS is spatially divided in a predetermined direction and includes a plurality of layers each including one or more SPCs. The encoding device and the decoding device encode or decode each SPC with reference to the SPC included in the same layer as the SPC or a layer lower than the SPC.

(4) The encoding device and the decoding device continuously encode or decode GOS within a world unit including a plurality of GOS. The encoding device and the decoding device write or read information indicating the order (direction) of encoding or decoding as metadata. That is, the encoded data includes information indicating the encoding order of a plurality of GOSs.

(4) The encoding device and the decoding device encode or decode two or more different spaces or GOSs in parallel with each other.

(4) The encoding device and the decoding device encode or decode space or spatial information (coordinates, size, etc.) of GOS.

In addition, the encoding device and the decoding device encode or decode a space or GOS included in a specific space specified based on external information regarding its own position or / and area size such as GPS, path information, or magnification. .

(4) The encoding device or the decoding device encodes or decodes a space far from its own position with a lower priority than a close space.

The encoding device sets one direction of the world according to the magnification or the application, and encodes a GOS having a layer structure in the direction. In addition, the decoding device decodes the GOS having a layer structure in one direction of the world set according to the magnification or the use from the lower layer preferentially.

The encoding device changes the feature points included in the space, the accuracy of object recognition, the size of the space area, and the like between the indoor and outdoor areas. However, the encoding device and the decoding device encode or decode an indoor GOS and an outdoor GOS whose coordinates are close to each other in the world adjacent to each other, and encode or decode these identifiers in association with each other.

(Embodiment 2)
When the encoded data of the point cloud is used in an actual device or service, it is desirable to transmit and receive necessary information according to the application in order to suppress the network bandwidth. However, until now, such a function did not exist in the encoding structure of three-dimensional data, and there was no encoding method therefor.

In the present embodiment, a three-dimensional data encoding method and a three-dimensional data encoding device for providing a function of transmitting and receiving only necessary information according to a use in encoded data of a three-dimensional point cloud, and A three-dimensional data decoding method and a three-dimensional data decoding device for decoding encoded data will be described.

ボ A voxel (VXL) having a certain amount of feature or more is defined as a feature voxel (FVXL), and a world (WLD) composed of FVXL is defined as a sparse world (SWLD). FIG. 11 is a diagram illustrating a configuration example of a sparse world and a world. SWLD includes FGOS, which is a GOS composed of FVXL, FSPC, which is an SPC composed of FVXL, and FVLM, which is a VLM composed of FVXL. The data structure and prediction structure of FGOS, FSPC and FVLM may be the same as those of GOS, SPC and VLM.

The feature amount is a feature amount that expresses three-dimensional position information of VXL or visible light information of the VXL position, and is a feature amount that is particularly detected at corners and edges of a three-dimensional object. Specifically, this feature amount is a three-dimensional feature amount or a visible light feature amount as described below, and any other feature amount representing the position, luminance, or color information of VXL can be used. It does not matter.

As the three-dimensional feature, a SHOT feature (Signature of Histograms of Orientations), a PFH feature (Point Feature Historygrams), or a PPF feature (Point Pair 量 Feature) is used.

The SHOT feature amount is obtained by dividing the periphery of VXL, calculating the inner product of the reference point and the normal vector of the divided region, and forming a histogram. This SHOT feature quantity has a feature that the number of dimensions is high and the feature expression power is high.

The PFH feature amount can be obtained by selecting a large number of two-point sets near VXL, calculating a normal vector from the two points, and forming a histogram. Since the PFH feature amount is a histogram feature, the PFH feature amount has a feature of being robust against some disturbance and having a high feature expression power.

The PPF feature amount is a feature amount calculated using a normal vector or the like for each of two VXLs. Since all VXLs are used for this PPF feature amount, it has robustness to occlusion.

In addition, as a feature amount of visible light, it is possible to use SIFT (Scale-Invariant Feature Transform), SURF (Speeded Up Robust Features), or HOG (Histogram of Oriented) using information such as luminance gradient information of an image. it can.

SWLD is generated by calculating the above-mentioned feature amount from each VXL of WLD and extracting FVXL. Here, the SWLD may be updated every time the WLD is updated, or the SWLD may be updated periodically after a predetermined time has elapsed, regardless of the update timing of the WLD.

SWLD may be generated for each feature value. For example, different SWLDs may be generated for each feature amount, such as SWLD1 based on the SHOT feature amount and SWLD2 based on the SIFT feature amount, and the SWLD may be used depending on the application. Further, the calculated feature value of each FVXL may be stored in each FVXL as feature value information.

Next, how to use Sparse World (SWLD) will be described. Since the SWLD includes only the feature voxel (FVXL), the data size is generally smaller than that of the WLD including all the VXLs.

(4) In an application that achieves a certain purpose by using a feature amount, by using information of SWLD instead of WLD, it is possible to suppress a read time from a hard disk, and a band and a transfer time during network transfer. For example, the network information and the transfer time can be suppressed by storing the WLD and the SWLD as the map information in the server and switching the map information to be transmitted to the WLD or the SWLD according to a request from the client. . Hereinafter, a specific example will be described.

FIGS. 12 and 13 are diagrams showing examples of using SWLD and WLD. As shown in FIG. 12, when the client 1, which is an in-vehicle device, needs map information for use in self-position determination, the client 1 sends a request to acquire map data for self-position estimation to the server (S301). The server transmits the SWLD to the client 1 according to the acquisition request (S302). The client 1 performs a self-position determination using the received SWLD (S303). At this time, the client 1 obtains VXL information around the client 1 by various methods such as a distance sensor such as a range finder, a stereo camera, or a combination of a plurality of monocular cameras, and obtains VXL information from the obtained VXL information and SWLD. Estimate location information. Here, the self-position information includes three-dimensional position information and orientation of the client 1.

As shown in FIG. 13, when the client 2, which is an in-vehicle device, needs map information for use in drawing a map such as a three-dimensional map, the client 2 sends a request to acquire map data for drawing a map to the server (S311). ). The server transmits the WLD to the client 2 according to the acquisition request (S312). The client 2 draws a map using the received WLD (S313). At this time, for example, the client 2 creates a rendering image using the image captured by the visible light camera or the like and the WLD acquired from the server, and draws the created image on a screen such as a car navigation system.

As described above, the server transmits the SWLD to the client in a case where the feature amount of each VXL is mainly required, such as self-position estimation, and transmits the WLD when detailed VXL information is required, such as map drawing. Send to client. This makes it possible to transmit and receive map data efficiently.

The client may determine by itself whether SWLD or WLD is necessary, and may request the server to transmit SWLD or WLD. Further, the server may determine whether to transmit SWLD or WLD according to the situation of the client or the network.

Next, a method of switching transmission and reception between the sparse world (SWLD) and the world (WLD) will be described.

か Whether to receive WLD or SWLD may be switched according to the network band. FIG. 14 is a diagram showing an operation example in this case. For example, when a low-speed network having a limited available network band is used in an LTE (Long Term Evolution) environment or the like, the client accesses the server via the low-speed network (S321), and sends the map from the server. The SWLD is acquired as information (S322). On the other hand, when a high-speed network having a sufficient network bandwidth is used in a Wi-Fi (registered trademark) environment or the like, the client accesses the server via the high-speed network (S323) and acquires the WLD from the server. (S324). Thereby, the client can acquire appropriate map information according to the network bandwidth of the client.

Specifically, the client receives the SWLD via LTE outdoors, and acquires the WLD via Wi-Fi (registered trademark) when entering the indoor such as a facility. This enables the client to acquire more detailed indoor map information.

As described above, the client may request the server for WLD or SWLD according to the bandwidth of the network used by the client. Alternatively, the client may transmit information indicating the bandwidth of the network used by the client to the server, and the server may transmit data (WLD or SWLD) suitable for the client according to the information. Alternatively, the server may determine the network bandwidth of the client and transmit data (WLD or SWLD) suitable for the client.

Alternatively, whether to receive WLD or SWLD may be switched according to the moving speed. FIG. 15 is a diagram showing an operation example in this case. For example, when the client is moving at high speed (S331), the client receives the SWLD from the server (S332). On the other hand, when the client is moving at low speed (S333), the client receives the WLD from the server (S334). This allows the client to acquire map information matching the speed while suppressing the network bandwidth. Specifically, the client can update rough map information at an appropriate speed by receiving SWLD having a small data amount while traveling on the highway. On the other hand, the client can acquire more detailed map information by receiving the WLD while traveling on a general road.

As described above, the client may request the server for WLD or SWLD according to its own moving speed. Alternatively, the client may transmit information indicating its own moving speed to the server, and the server may transmit data (WLD or SWLD) suitable for the client according to the information. Alternatively, the server may determine the moving speed of the client and transmit data (WLD or SWLD) suitable for the client.

{Circle around (1)} The client may first obtain the SWLD from the server, and then obtain the WLD of the important area. For example, when acquiring map data, the client first obtains rough map information by SWLD, narrows down an area in which many features such as buildings, signs, or people appear, and WLD of the narrowed-down area. Retrieve later. As a result, the client can acquire detailed information of a necessary area while suppressing the amount of data received from the server.

Also, the server may create a separate SWLD for each object from the WLD, and the client may receive each according to the application. Thereby, the network band can be suppressed. For example, the server recognizes a person or a car in advance from the WLD and creates a SWLD of the person and a SWLD of the car. The client receives the SWLD of the person when he / she wants to obtain information on the surrounding people, and receives the SWLD of the car when he / she wants to obtain information on the car. Further, such a type of SWLD may be distinguished by information (flag, type, or the like) added to a header or the like.

Next, the configuration and operation flow of the three-dimensional data encoding device (for example, a server) according to the present embodiment will be described. FIG. 16 is a block diagram of a three-dimensional data encoding device 400 according to the present embodiment. FIG. 17 is a flowchart of a three-dimensional data encoding process performed by the three-dimensional data encoding device 400.

The three-dimensional data encoding device 400 illustrated in FIG. 16 encodes the input three-dimensional data 411 to generate encoded three-

dimensional data

413 and 414 that are encoded streams. Here, the encoded three-dimensional data 413 is encoded three-dimensional data corresponding to WLD, and the encoded three-dimensional data 414 is encoded three-dimensional data corresponding to SWLD. The three-dimensional data encoding device 400 includes an acquisition unit 401, an encoding region determination unit 402, a SWLD extraction unit 403, a WLD encoding unit 404, and a SWLD encoding unit 405.

As shown in FIG. 17, first, the obtaining unit 401 obtains input three-dimensional data 411 that is point cloud data in a three-dimensional space (S401).

Next, the coding region determination unit 402 determines a coding target space region based on the space region where the point cloud data exists (S402).

Next, the SWLD extraction unit 403 defines a spatial region to be encoded as a WLD, and calculates a feature amount from each VXL included in the WLD. Then, the SWLD extraction unit 403 generates extracted three-dimensional data 412 by extracting VXL having a feature amount equal to or greater than a predetermined threshold, defining the extracted VXL as FVXL, and adding the FVXL to SWLD. (S403). That is, extracted three-dimensional data 412 whose feature amount is equal to or larger than the threshold is extracted from the input three-dimensional data 411.

Next, the WLD encoding unit 404 generates encoded three-dimensional data 413 corresponding to WLD by encoding the input three-dimensional data 411 corresponding to WLD (S404). At this time, the WLD encoding unit 404 adds information for distinguishing that the encoded three-dimensional data 413 is a stream including WLD to the header of the encoded three-dimensional data 413.

{Circle around (4)} The SWLD encoding unit 405 generates encoded three-dimensional data 414 corresponding to SWLD by encoding the extracted three-dimensional data 412 corresponding to SWLD. At this time, the SWLD encoding unit 405 adds, to the header of the encoded three-dimensional data 414, information for distinguishing that the encoded three-dimensional data 414 is a stream including SWLD.

Note that the processing order of the process of generating the encoded three-dimensional data 413 and the process of generating the encoded three-dimensional data 414 may be reversed. Also, some or all of these processes may be performed in parallel.

パラメータ As information to be added to the header of the encoded three-

dimensional data

413 and 414, for example, a parameter “world_type” is defined. If world_type = 0, it indicates that the stream includes WLD, and if world_type = 1, it indicates that the stream includes SWLD. Further, when defining many other types, the numerical value to be assigned may be increased, such as world_type = 2. Further, one of the encoded three-

dimensional data

413 and 414 may include a specific flag. For example, a flag indicating that the stream includes SWLD may be added to the encoded three-dimensional data 414. In this case, the decoding device can determine whether the stream includes the WLD or the stream including the SWLD based on the presence or absence of the flag.

The coding method used when the WLD coding unit 404 codes the WLD may be different from the coding method used when the SWLD coding unit 405 codes the SWLD.

For example, since data is thinned out in SWLD, there is a possibility that the correlation with peripheral data is lower than in WLD. Therefore, in the encoding method used for SWLD, inter prediction among intra prediction and inter prediction may be given priority over the encoding method used for WLD.

Also, the coding method used for SWLD and the coding method used for WLD may have different three-dimensional position expression methods. For example, in SWLD, a three-dimensional position of FVXL may be represented by three-dimensional coordinates, and in WLD, a three-dimensional position may be represented by an octree described later, or vice versa.

(4) The SWLD encoding unit 405 performs encoding such that the data size of the SWLD encoded three-dimensional data 414 is smaller than the data size of the WLD encoded three-dimensional data 413. For example, as described above, SWLD may have lower correlation between data than WLD. As a result, the encoding efficiency may decrease, and the data size of the encoded three-dimensional data 414 may be larger than the data size of the encoded three-dimensional data 413 of the WLD. Therefore, if the data size of the obtained encoded three-dimensional data 414 is larger than the data size of the encoded three-dimensional data 413 of the WLD, the SWLD encoding unit 405 performs re-encoding to obtain the data size. Is re-generated.

{For example, the SWLD extracting unit 403 regenerates the extracted three-dimensional data 412 in which the number of feature points to be extracted is reduced, and the SWLD encoding unit 405 encodes the extracted three-dimensional data 412. Alternatively, the degree of quantization in SWLD encoding section 405 may be made coarser. For example, in an octree structure to be described later, the degree of quantization can be reduced by rounding the data in the lowermost layer.

If the data size of the SWLD encoded three-dimensional data 414 cannot be made smaller than the data size of the WLD encoded three-dimensional data 413, the SWLD encoding unit 405 does not generate the SWLD encoded three-dimensional data 414. May be. Alternatively, the encoded three-dimensional data 413 of the WLD may be copied to the encoded three-dimensional data 414 of the SWLD. That is, the encoded three-dimensional data 413 of WLD may be used as it is as the encoded three-dimensional data 414 of SWLD.

Next, the configuration and operation flow of the three-dimensional data decoding device (eg, client) according to the present embodiment will be described. FIG. 18 is a block diagram of a three-dimensional data decoding device 500 according to the present embodiment. FIG. 19 is a flowchart of the three-dimensional data decoding process performed by the three-dimensional data decoding device 500.

The three-dimensional data decoding device 500 illustrated in FIG. 18 generates the decoded three-

dimensional data

512 or 513 by decoding the encoded three-dimensional data 511. Here, the encoded three-dimensional data 511 is, for example, the encoded three-

dimensional data

413 or 414 generated by the three-dimensional data encoding device 400.

The three-dimensional data decoding device 500 includes an acquisition unit 501, a header analysis unit 502, a WLD decoding unit 503, and a SWLD decoding unit 504.

As shown in FIG. 19, first, the acquiring unit 501 acquires the encoded three-dimensional data 511 (S501). Next, the header analysis unit 502 analyzes the header of the encoded three-dimensional data 511, and determines whether the encoded three-dimensional data 511 is a stream including WLD or a stream including SWLD (S502). For example, the parameter of the above-described world_type is referred to, and the determination is performed.

When the encoded three-dimensional data 511 is a stream including WLD (Yes in S503), the WLD decoding unit 503 generates the WLD decoded three-dimensional data 512 by decoding the encoded three-dimensional data 511 (S504). . On the other hand, when the encoded three-dimensional data 511 is a stream including SWLD (No in S503), the SWLD decoding unit 504 generates the SWLD decoded three-dimensional data 513 by decoding the encoded three-dimensional data 511 ( S505).

Also, similarly to the encoding device, the decoding method used when the WLD decoding unit 503 decodes the WLD may be different from the decoding method used when the SWLD decoding unit 504 decodes the SWLD. For example, in the decoding method used for SWLD, inter prediction among intra prediction and inter prediction may be given priority over the decoding method used for WLD.

Also, the decoding method used for SWLD and the decoding method used for WLD may have different three-dimensional position expression methods. For example, in SWLD, a three-dimensional position of FVXL may be represented by three-dimensional coordinates, and in WLD, a three-dimensional position may be represented by an octree described later, or vice versa.

Next, an octree expression, which is a three-dimensional position expression method, will be described. The VXL data included in the three-dimensional data is converted into an octree structure and then encoded. FIG. 20 is a diagram illustrating an example of the VXL of the WLD. FIG. 21 is a diagram showing the octree structure of the WLD shown in FIG. In the example shown in FIG. 20, there are three VXL1 to VXL3, which are VXLs including a point group (hereinafter, valid VXLs). As shown in FIG. 21, the octree structure includes nodes and leaves. Each node has up to eight nodes or leaves. Each leaf has VXL information. Here, among the leaves shown in FIG. 21, leaves 1, 2, and 3 represent VXL1, VXL2, and VXL3 shown in FIG. 20, respectively.

Specifically, each node and leaf corresponds to a three-dimensional position. Node 1 corresponds to the entire block shown in FIG. The block corresponding to the node 1 is divided into eight blocks. Of the eight blocks, the block containing the effective VXL is set as a node, and the other blocks are set as leaves. The block corresponding to the node is further divided into eight nodes or leaves, and this processing is repeated for the tree structure hierarchy. Also, the blocks at the bottom are all set as leaves.

FIG. 22 is a diagram showing an example of a SWLD generated from the WLD shown in FIG. VXL1 and VXL2 shown in FIG. 20 are determined as FVXL1 and FVXL2 as a result of the feature amount extraction, and are added to SWLD. On the other hand, VXL3 is not determined as FVXL and is not included in SWLD. FIG. 23 is a diagram showing an octree structure of the SWLD shown in FIG. In the octree structure shown in FIG. 23, the leaf 3 corresponding to VXL3 shown in FIG. 21 is deleted. As a result, the node 3 shown in FIG. 21 has no valid VXL and has been changed to a leaf. As described above, the number of leaves of SWLD is generally smaller than the number of leaves of WLD, and the encoded three-dimensional data of SWLD is also smaller than the encoded three-dimensional data of WLD.

Hereinafter, a modified example of the present embodiment will be described.

For example, a client such as an in-vehicle device receives a SWLD from the server when performing self-position estimation, performs self-position estimation using SWLD, and performs a distance sensor such as a range finder or a stereo when performing obstacle detection. Obstacle detection may be performed based on surrounding three-dimensional information acquired by oneself using various methods such as a camera or a combination of a plurality of monocular cameras.

(4) In general, VLD data of a flat region is hardly included in SWLD. Therefore, the server may hold a sub-sampled world (subWLD) obtained by sub-sampling the WLD for detecting a static obstacle, and transmit the SWLD and the subWLD to the client. This allows the client to perform self-position estimation and obstacle detection while suppressing the network bandwidth.

クライアント Also, when a client draws three-dimensional map data at high speed, it may be more convenient for the map information to have a mesh structure. Therefore, the server may generate a mesh from the WLD and hold the mesh as a mesh world (MWLD) in advance. For example, the client receives MWLD when coarse three-dimensional rendering is required, and receives WLD when detailed three-dimensional rendering is required. Thereby, the network band can be suppressed.

{Circle around (4)} Although the server sets the VXL whose feature amount is equal to or larger than the threshold value to the FVXL among the VXLs, the server may calculate the FVXL by a different method. For example, the server determines that VXL, VLM, SPC, or GOS forming a signal or an intersection is necessary for self-position estimation, driving assistance, automatic driving, or the like, and includes the SWLD as FVXL, FVLM, FSPC, or FGOS. It does not matter. Further, the above determination may be made manually. The FVXL or the like obtained by the above method may be added to the FVXL or the like set based on the feature amount. That is, the SWLD extraction unit 403 may further extract data corresponding to an object having a predetermined attribute from the input three-dimensional data 411 as the extracted three-dimensional data 412.

旨 Also, the fact that they are necessary for those uses may be labeled separately from the feature amount. In addition, the server may separately hold FVXL necessary for self-position estimation such as a signal or an intersection, driving assistance, or automatic driving as an upper layer (for example, a lane world) of SWLD.

The server may add an attribute to the VXL in the WLD for each random access unit or for each predetermined unit. The attribute includes, for example, information indicating whether it is necessary or unnecessary for the self-position estimation or information indicating whether it is important as traffic information such as a signal or an intersection. Further, the attribute may include a correspondence relationship with a feature (intersection, road, or the like) in lane information (GDF: Geographic Data Data Files, etc.).

Alternatively, the following method may be used as a method for updating WLD or SWLD.

Update information indicating changes in people, construction, or trees (for trucks) is uploaded to the server as point clouds or metadata. The server updates the WLD based on the upload, and then updates the SWLD using the updated WLD.

Also, when the client detects inconsistency between the three-dimensional information generated by itself and the three-dimensional information received from the server at the time of self-position estimation, the client may transmit the three-dimensional information generated by itself to the server together with the update notification. Good. In this case, the server updates SWLD using WLD. If the SWLD is not updated, the server determines that the WLD itself is old.

In addition, it is assumed that information for distinguishing between WLD and SWLD is added as header information of the coded stream. For example, when there are many types of worlds such as a mesh world or a lane world, these are distinguished. Information may be added to the header information. Further, when there are many SWLDs having different feature amounts, information for distinguishing each SWLD may be added to the header information.

Although the SWLD is configured by FVXL, the SWLD may include VXL not determined as FVXL. For example, the SWLD may include an adjacent VXL used when calculating the feature amount of the FVXL. Thus, even when the feature amount information is not added to each FVXL of the SWLD, the client can calculate the feature amount of the FVXL when receiving the SWLD. In this case, the SWLD may include information for distinguishing whether each VXL is FVXL or VXL.

As described above, the three-dimensional data encoding device 400 extracts and extracts the extracted three-dimensional data 412 (second three-dimensional data) having the feature value equal to or larger than the threshold from the input three-dimensional data 411 (first three-dimensional data). By encoding the three-dimensional data 412, encoded three-dimensional data 414 (first encoded three-dimensional data) is generated.

According to this, the three-dimensional data encoding device 400 generates encoded three-dimensional data 414 obtained by encoding data whose feature amount is equal to or larger than the threshold value. As a result, the data amount can be reduced as compared with the case where the input three-dimensional data 411 is directly encoded. Therefore, the three-dimensional data encoding device 400 can reduce the amount of data to be transmitted.

(3) The three-dimensional data encoding device 400 further generates encoded three-dimensional data 413 (second encoded three-dimensional data) by encoding the input three-dimensional data 411.

According to this, the three-dimensional data encoding device 400 can selectively transmit the encoded three-dimensional data 413 and the encoded three-dimensional data 414 according to, for example, a use purpose.

{The extracted three-dimensional data 412 is encoded by the first encoding method, and the input three-dimensional data 411 is encoded by the second encoding method different from the first encoding method.

According to this, the three-dimensional data encoding device 400 can use an encoding method suitable for the input three-dimensional data 411 and the extracted three-dimensional data 412, respectively.

In addition, in the first encoding method, the inter prediction among the intra prediction and the inter prediction has priority over the second encoding method.

According to this, the three-dimensional data encoding device 400 can increase the priority of the inter prediction with respect to the extracted three-dimensional data 412 in which the correlation between adjacent data tends to be low.

Also, the first encoding method and the second encoding method have different three-dimensional position expression methods. For example, in the second encoding method, a three-dimensional position is represented by an octree, and in the first encoding method, a three-dimensional position is represented by three-dimensional coordinates.

According to this, the three-dimensional data encoding device 400 can use a more appropriate three-dimensional position expression method for three-dimensional data having different numbers of data (the number of VXL or FVXL).

In addition, at least one of the encoded three-

dimensional data

413 and 414 is whether the encoded three-dimensional data is encoded three-dimensional data obtained by encoding the input three-dimensional data 411, or Includes an identifier indicating whether the data is encoded three-dimensional data obtained by encoding a part of the data. That is, the identifier indicates whether the encoded three-dimensional data is the encoded three-dimensional data 413 of WLD or the encoded three-dimensional data 414 of SWLD.

According to this, the decoding device can easily determine whether the acquired encoded three-dimensional data is the encoded three-dimensional data 413 or the encoded three-dimensional data 414.

(3) The three-dimensional data encoding device 400 encodes the extracted three-dimensional data 412 such that the data amount of the encoded three-dimensional data 414 is smaller than the data amount of the encoded three-dimensional data 413.

According to this, the three-dimensional data encoding device 400 can make the data amount of the encoded three-dimensional data 414 smaller than the data amount of the encoded three-dimensional data 413.

{Circle around (3)} The three-dimensional data encoding device 400 further extracts data corresponding to an object having a predetermined attribute from the input three-dimensional data 411 as extracted three-dimensional data 412. For example, an object having a predetermined attribute is an object necessary for self-position estimation, driving assistance, automatic driving, or the like, such as a signal or an intersection.

According to this, the three-dimensional data encoding device 400 can generate encoded three-dimensional data 414 including data required by the decoding device.

(3) The three-dimensional data encoding device 400 (server) further transmits one of the encoded three-

dimensional data

413 and 414 to the client according to the state of the client.

According to this, the three-dimensional data encoding device 400 can transmit appropriate data according to the state of the client.

クライアント The status of the client includes the communication status of the client (for example, network bandwidth) or the moving speed of the client.

(3) The three-dimensional data encoding device 400 further transmits one of the encoded three-

dimensional data

413 and 414 to the client in response to a request from the client.

According to this, the three-dimensional data encoding device 400 can transmit appropriate data according to a request from the client.

The three-dimensional data decoding device 500 according to the present embodiment decodes the encoded three-

dimensional data

413 or 414 generated by the three-dimensional data encoding device 400.

That is, the three-dimensional data decoding device 500 performs the first decoding on the encoded three-dimensional data 414 obtained by encoding the extracted three-dimensional data 412 having the feature amount extracted from the input three-dimensional data 411 that is equal to or larger than the threshold value. Decrypt by the method. In addition, the three-dimensional data decoding device 500 decodes the encoded three-dimensional data 413 obtained by encoding the input three-dimensional data 411, using a second decoding method different from the first decoding method.

According to this, the three-dimensional data decoding apparatus 500 selects the encoded three-dimensional data 414 and the encoded three-dimensional data 413 obtained by encoding the data whose feature amount is equal to or larger than the threshold value, for example, according to the intended use. Can be received. Thereby, the three-dimensional data decoding device 500 can reduce the amount of data to be transmitted. Further, the three-dimensional data decoding device 500 can use a decoding method suitable for the input three-dimensional data 411 and the extracted three-dimensional data 412, respectively.

インター In the first decoding method, inter prediction among intra prediction and inter prediction has priority over the second decoding method.

According to this, the three-dimensional data decoding device 500 can increase the priority of the inter prediction for the extracted three-dimensional data in which the correlation between adjacent data is likely to be low.

Also, the first decoding method and the second decoding method are different in the method of expressing the three-dimensional position. For example, for example, in the second decoding method, a three-dimensional position is represented by an octree, and in the first decoding method, a three-dimensional position is represented by three-dimensional coordinates.

According to this, the three-dimensional data decoding device 500 can use a more suitable three-dimensional position expression method for three-dimensional data having different numbers of data (the number of VXL or FVXL).

In addition, at least one of the encoded three-

dimensional data

413 and 414 is whether the encoded three-dimensional data is encoded three-dimensional data obtained by encoding the input three-dimensional data 411, or Includes an identifier indicating whether the data is encoded three-dimensional data obtained by encoding a part of the data. The three-dimensional data decoding device 500 identifies the encoded three-

dimensional data

413 and 414 with reference to the identifier.

According to this, the three-dimensional data decoding device 500 can easily determine whether the acquired encoded three-dimensional data is the encoded three-dimensional data 413 or the encoded three-dimensional data 414.

(3) The three-dimensional data decoding device 500 further notifies the server of the status of the client (the three-dimensional data decoding device 500). The three-dimensional data decoding device 500 receives one of the encoded three-

dimensional data

413 and 414 transmitted from the server according to the state of the client.

According to this, the three-dimensional data decoding device 500 can receive appropriate data according to the state of the client.

Further, the three-dimensional data decoding device 500 further requests one of the encoded three-

dimensional data

413 and 414 from the server, and in response to the request, transmits one of the encoded three-

dimensional data

413 and 414 transmitted from the server. Receive.

According to this, the three-dimensional data decoding device 500 can receive appropriate data according to the application.

(Embodiment 3)
In the present embodiment, a method for transmitting and receiving three-dimensional data between vehicles will be described. For example, three-dimensional data is transmitted and received between the own vehicle and the surrounding vehicles.

FIG. 24 is a block diagram of a three-dimensional data creation device 620 according to the present embodiment. The three-dimensional data creation device 620 is, for example, more dense by combining the received second three-dimensional data 635 with the first three-dimensional data 632 included in the own vehicle and created by the three-dimensional data creation device 620. The third three-dimensional data 636 is created.

The three-dimensional data creation device 620 includes a three-dimensional data creation unit 621, a request range determination unit 622, a search unit 623, a reception unit 624, a decoding unit 625, and a synthesis unit 626.

First, the three-dimensional data creation unit 621 creates the first three-dimensional data 632 using the sensor information 631 detected by a sensor included in the own vehicle. Next, the required range determining unit 622 determines a required range that is a three-dimensional space range in which data is insufficient in the created first three-dimensional data 632.

Next, the search unit 623 searches for a nearby vehicle that owns the three-dimensional data of the required range, and transmits required range information 633 indicating the required range to the peripheral vehicle specified by the search. Next, the receiving unit 624 receives coded three-dimensional data 634, which is a coded stream of the required range, from the surrounding vehicles (S624). In addition, the search unit 623 may indiscriminately issue requests to all vehicles existing in the specific range and receive the encoded three-dimensional data 634 from the responding partner. Further, the search unit 623 may issue a request to an object such as a traffic light or a sign, not limited to the vehicle, and receive the encoded three-dimensional data 634 from the object.

Next, the decoding unit 625 obtains the second three-dimensional data 635 by decoding the received encoded three-dimensional data 634. Next, the combining unit 626 combines the first three-dimensional data 632 and the second three-dimensional data 635 to create denser third three-dimensional data 636.

Next, the configuration and operation of the three-dimensional data transmission device 640 according to the present embodiment will be described. FIG. 25 is a block diagram of the three-dimensional data transmission device 640.

The three-dimensional data transmission device 640 converts the fifth three-dimensional data 652 included in the above-described surrounding vehicle and created by the surrounding vehicle into sixth three-dimensional data 654 required by the own vehicle, and outputs the sixth three-dimensional data By encoding 654, encoded three-dimensional data 634 is generated, and the encoded three-dimensional data 634 is transmitted to the host vehicle.

The three-dimensional data transmitting device 640 includes a three-dimensional data creating unit 641, a receiving unit 642, an extracting unit 643, an encoding unit 644, and a transmitting unit 645.

First, the three-dimensional data creation unit 641 creates the fifth three-dimensional data 652 using the sensor information 651 detected by a sensor included in the surrounding vehicle. Next, the receiving unit 642 receives the request range information 633 transmitted from the own vehicle.

Next, the extracting unit 643 processes the fifth three-dimensional data 652 into the sixth three-dimensional data 654 by extracting the three-dimensional data of the required range indicated by the required range information 633 from the fifth three-dimensional data 652. I do. Next, the encoding unit 644 encodes the sixth three-dimensional data 654 to generate encoded three-dimensional data 634 that is an encoded stream. Then, the transmitting unit 645 transmits the encoded three-dimensional data 634 to the own vehicle.

Here, an example will be described in which the own vehicle includes the three-dimensional data generation device 620 and the surrounding vehicles include the three-dimensional data transmission device 640. However, each vehicle includes the three-dimensional data generation device 620 and the three-dimensional data transmission device. 640 may be provided.

(Embodiment 4)
In the present embodiment, an operation of an abnormal system in self-position estimation based on a three-dimensional map will be described.

用途 It is expected that applications such as automatic driving of cars or autonomous movement of moving objects such as robots and flying objects such as drones will be expanded in the future. As an example of means for realizing such autonomous movement, there is a method in which a moving body travels according to a map while estimating its own position in a three-dimensional map (self-position estimation).

The self-position estimation is performed by matching a three-dimensional map with three-dimensional information around the own vehicle acquired by a sensor such as a range finder (eg, LiDAR) mounted on the own vehicle or a stereo camera (hereinafter, three-dimensional data detected by the own vehicle). Then, it can be realized by estimating the position of the own vehicle in the three-dimensional map.

The three-dimensional map changes not only in a three-dimensional point cloud, but also in two-dimensional map data such as road and intersection shape information, such as the HD map proposed by HERE, or in real time such as traffic jams and accidents. Information may be included. A three-dimensional map is composed of a plurality of layers such as three-dimensional data, two-dimensional data, and metadata that changes in real time, and the device can also acquire or refer to only necessary data.

The data of the point cloud may be the SWLD described above, or may include point cloud data that is not a feature point. Further, transmission and reception of data of the point cloud are performed on the basis of one or a plurality of random access units.

The following method can be used as a matching method between the three-dimensional map and the vehicle detection three-dimensional data. For example, the apparatus compares the shapes of point clouds in each other's point clouds, and determines that a portion having a high degree of similarity between feature points is at the same position. Further, when the three-dimensional map is composed of SWLDs, the matching is performed by comparing the feature points composing the SWLD with the three-dimensional feature points extracted from the vehicle detection three-dimensional data.

Here, in order to perform the self-position estimation with high accuracy, (A) the three-dimensional map and the own-vehicle detection three-dimensional data have been obtained, and (B) their accuracy satisfies a predetermined standard. It is necessary. However, in the following abnormal cases, (A) or (B) cannot be satisfied.

(1) A three-dimensional map cannot be obtained via communication.

(2) The three-dimensional map does not exist or the three-dimensional map has been acquired but is damaged.

(3) The sensor of the own vehicle is out of order or the accuracy of generating the three-dimensional data for detecting the own vehicle is insufficient due to bad weather.

動作 The operation to deal with these abnormal cases will be described below. Hereinafter, the operation will be described using a car as an example, but the following method can be applied to all moving objects that move autonomously, such as a robot or a drone.

Hereinafter, the configuration and operation of the three-dimensional information processing apparatus according to the present embodiment for dealing with an abnormal case in the three-dimensional map or the three-dimensional data detected by the vehicle will be described. FIG. 26 is a block diagram illustrating a configuration example of a three-dimensional information processing device 700 according to the present embodiment.

The three-dimensional information processing device 700 is mounted on a moving object such as a car, for example. As illustrated in FIG. 26, the three-dimensional information processing device 700 includes a three-dimensional map acquisition unit 701, a vehicle detection data acquisition unit 702, an abnormal case determination unit 703, a coping operation determination unit 704, and an operation control unit 705. And

Note that the three-dimensional information processing apparatus 700 is not illustrated for detecting a structure or a moving object around the own vehicle, such as a camera for acquiring a two-dimensional image or a sensor for one-dimensional data using ultrasonic waves or lasers. A two-dimensional or one-dimensional sensor may be provided. In addition, the three-dimensional information processing device 700 may include a communication unit (not shown) for acquiring a three-dimensional map by a mobile communication network such as 4G or 5G, or by vehicle-to-vehicle communication or road-to-vehicle communication. .

The three-dimensional map acquisition unit 701 acquires the three-dimensional map 711 near the traveling route. For example, the three-dimensional map acquisition unit 701 acquires the three-dimensional map 711 through a mobile communication network, or vehicle-to-vehicle communication or road-to-vehicle communication.

Next, the own vehicle detection data acquisition unit 702 acquires the own vehicle detection three-dimensional data 712 based on the sensor information. For example, the own-vehicle detection data acquisition unit 702 generates the own-vehicle detection three-dimensional data 712 based on sensor information acquired by a sensor included in the own vehicle.

Next, the abnormal case determination unit 703 detects an abnormal case by performing a predetermined check on at least one of the acquired three-dimensional map 711 and the own vehicle detection three-dimensional data 712. That is, the abnormal case determination unit 703 determines whether at least one of the acquired three-dimensional map 711 and the own vehicle detection three-dimensional data 712 is abnormal.

If an abnormal case is detected, the coping operation determination unit 704 determines a coping operation for the abnormal case. Next, the operation control unit 705 controls the operation of each processing unit necessary for performing the coping operation, such as the three-dimensional map acquisition unit 701.

On the other hand, if no abnormal case is detected, the three-dimensional information processing device 700 ends the processing.

{Circle around (3)} The three-dimensional information processing device 700 uses the three-dimensional map 711 and the vehicle detection three-dimensional data 712 to estimate the position of the vehicle including the three-dimensional information processing device 700. Next, the three-dimensional information processing device 700 automatically drives the vehicle using the result of the self-position estimation.

As described above, the three-dimensional information processing apparatus 700 acquires map data (three-dimensional map 711) including the first three-dimensional position information via the communication path. For example, the first three-dimensional position information is encoded in units of a subspace having three-dimensional coordinate information, each of which is a set of one or more subspaces, and a plurality of random numbers each of which can be independently decoded. Includes access units. For example, the first three-dimensional position information is data (SWLD) in which a feature point whose three-dimensional feature amount is equal to or more than a predetermined threshold is encoded.

{Circle around (3)} The three-dimensional information processing device 700 generates second three-dimensional position information (own vehicle detection three-dimensional data 712) from information detected by the sensor. Next, the three-dimensional information processing device 700 performs an abnormality determination process on the first three-dimensional position information or the second three-dimensional position information, thereby obtaining the first three-dimensional position information or the second three-dimensional position information. It is determined whether the three-dimensional position information is abnormal.

When the first three-dimensional position information or the second three-dimensional position information is determined to be abnormal, the three-dimensional information processing apparatus 700 determines an action to cope with the abnormality. Next, the three-dimensional information processing device 700 performs control necessary for performing the coping operation.

Accordingly, the three-dimensional information processing apparatus 700 can detect an abnormality in the first three-dimensional position information or the second three-dimensional position information and perform a coping operation.

(Embodiment 5)
In the present embodiment, a method of transmitting three-dimensional data to a following vehicle and the like will be described.

FIG. 27 is a block diagram showing a configuration example of a three-dimensional data creation device 810 according to the present embodiment. The three-dimensional data creation device 810 is mounted on, for example, a vehicle. The three-dimensional data creation device 810 transmits and receives three-dimensional data to and from an external traffic monitoring cloud, a preceding vehicle or a following vehicle, and creates and accumulates three-dimensional data.

The three-dimensional data creation device 810 includes a data reception unit 811, a communication unit 812, a reception control unit 813, a format conversion unit 814, a plurality of sensors 815, a three-dimensional data creation unit 816, a three-dimensional data synthesis unit 817, a three-dimensional data storage unit 818, a communication unit 819, a transmission control unit 820, a format conversion unit 821, and a data transmission unit 822.

The data receiving unit 811 receives the three-dimensional data 831 from the traffic monitoring cloud or the preceding vehicle. The three-dimensional data 831 includes, for example, information such as a point cloud, a visible light image, depth information, sensor position information, or speed information including an area that cannot be detected by the sensor 815 of the vehicle.

The communication unit 812 communicates with the traffic monitoring cloud or the preceding vehicle, and transmits a data transmission request or the like to the traffic monitoring cloud or the preceding vehicle.

(4) The reception control unit 813 exchanges information such as a compatible format with the communication destination via the communication unit 812, and establishes communication with the communication destination.

The format conversion unit 814 generates three-dimensional data 832 by performing format conversion and the like on the three-dimensional data 831 received by the data receiving unit 811. When the three-dimensional data 831 is compressed or encoded, the format conversion unit 814 performs a decompression or decoding process.

The plurality of sensors 815 are a group of sensors such as a LiDAR, a visible light camera, and an infrared camera that acquire information outside the vehicle, and generate the sensor information 833. For example, when the sensor 815 is a laser sensor such as LiDAR, the sensor information 833 is three-dimensional data such as a point cloud (point cloud data). Note that the number of sensors 815 need not be plural.

The three-dimensional data creating unit 816 creates three-dimensional data 834 from the sensor information 833. The three-dimensional data 834 includes, for example, information such as a point cloud, a visible light image, depth information, sensor position information, or speed information.

The three-dimensional data synthesizing unit 817 synthesizes the three-dimensional data 834 generated based on the sensor information 833 of the own vehicle with the three-dimensional data 832 generated by the traffic monitoring cloud or the preceding vehicle, etc. The three-dimensional data 835 including the space ahead of the preceding vehicle that cannot be detected by the sensor 815 is constructed.

The three-dimensional data storage unit 818 stores the generated three-dimensional data 835 and the like.

The communication unit 819 communicates with the traffic monitoring cloud or the following vehicle, and transmits a data transmission request or the like to the traffic monitoring cloud or the following vehicle.

The transmission control unit 820 exchanges information such as a compatible format with a communication destination via the communication unit 819, and establishes communication with the communication destination. Further, the transmission control unit 820 determines a space in the transmission target three-dimensional data based on the three-dimensional data construction information of the three-dimensional data 832 generated by the three-dimensional data synthesis unit 817 and the data transmission request from the communication destination. Determine a certain transmission area.

{Specifically, the transmission control unit 820 determines a transmission area including a space in front of the own vehicle that cannot be detected by the sensor of the following vehicle, in response to a data transmission request from the traffic monitoring cloud or the following vehicle. In addition, the transmission control unit 820 determines the transmission area by determining whether or not the transmittable space or the transmitted space is updated based on the three-dimensional data construction information. For example, the transmission control unit 820 determines the area specified by the data transmission request and in which the corresponding three-dimensional data 835 exists as the transmission area. Then, the transmission control unit 820 notifies the format conversion unit 821 of the format and the transmission area corresponding to the communication destination.

The format conversion unit 821 converts the three-dimensional data 837 of the transmission area out of the three-dimensional data 835 stored in the three-dimensional data storage unit 818 into a format supported by the receiving side, thereby converting the three-dimensional data 837. Generate. Note that the format conversion unit 821 may reduce the data amount by compressing or encoding the three-dimensional data 837.

The data transmission unit 822 transmits the three-dimensional data 837 to the traffic monitoring cloud or the following vehicle. The three-dimensional data 837 includes, for example, information such as a point cloud in front of the own vehicle, a visible light image, depth information, or sensor position information, including a blind spot of the following vehicle.

Here, an example in which format conversion and the like are performed in the

format conversion units

814 and 821 has been described here, but format conversion may not be performed.

With such a configuration, the three-dimensional data creation device 810 acquires the three-dimensional data 831 in an area that cannot be detected by the sensor 815 of the own vehicle from the outside, and outputs the three-dimensional data 831 and the sensor information 833 detected by the sensor 815 of the own vehicle. The three-dimensional data 835 is generated by combining the three-dimensional data 834 with the three-dimensional data 834 based on. Accordingly, the three-dimensional data creation device 810 can generate three-dimensional data in a range that cannot be detected by the sensor 815 of the own vehicle.

Further, the three-dimensional data creation device 810, in response to a data transmission request from the traffic monitoring cloud or the following vehicle, converts the three-dimensional data including the space in front of the own vehicle that cannot be detected by the sensor of the following vehicle into the traffic monitoring cloud or the following It can be transmitted to vehicles and the like.

(Embodiment 6)
In the fifth embodiment, an example has been described in which a client device such as a vehicle transmits three-dimensional data to another vehicle or a server such as a traffic monitoring cloud. In this embodiment, a client device transmits sensor information obtained by a sensor to a server or another client device.

First, the configuration of the system according to the present embodiment will be described. FIG. 28 is a diagram illustrating a configuration of a transmission / reception system of a three-dimensional map and sensor information according to the present embodiment. This system includes a server 901 and

client devices

902A and 902B. Note that the

client devices

902A and 902B are also referred to as client devices 902 unless otherwise distinguished.

The client device 902 is, for example, an in-vehicle device mounted on a moving body such as a vehicle. The server 901 is, for example, a traffic monitoring cloud or the like, and can communicate with a plurality of client devices 902.

The server 901 transmits the three-dimensional map composed of the point cloud to the client device 902. Note that the configuration of the three-dimensional map is not limited to the point cloud, and may represent other three-dimensional data such as a mesh structure.

The client device 902 transmits the sensor information acquired by the client device 902 to the server 901. The sensor information includes, for example, at least one of LiDAR acquisition information, a visible light image, an infrared image, a depth image, sensor position information, and speed information.

Data transmitted and received between the server 901 and the client device 902 may be compressed for data reduction, or may be left uncompressed to maintain data accuracy. When compressing data, for example, a three-dimensional compression method based on an octree structure can be used for the point cloud. Further, a two-dimensional image compression method can be used for the visible light image, the infrared image, and the depth image. The two-dimensional image compression method is, for example, MPEG-4 @ AVC or HEVC standardized by MPEG.

{Circle around (3)} The server 901 transmits a three-dimensional map managed by the server 901 to the client device 902 in response to a transmission request of the three-dimensional map from the client device 902. The server 901 may transmit the three-dimensional map without waiting for the transmission request of the three-dimensional map from the client device 902. For example, the server 901 may broadcast the three-dimensional map to one or more client devices 902 in a predetermined space. Further, the server 901 may transmit a three-dimensional map suitable for the position of the client device 902 at regular time intervals to the client device 902 that has received the transmission request once. The server 901 may transmit the three-dimensional map to the client device 902 every time the three-dimensional map managed by the server 901 is updated.

The client device 902 issues a request for transmitting a three-dimensional map to the server 901. For example, when the client device 902 wants to perform self-position estimation during traveling, the client device 902 transmits a request for transmitting a three-dimensional map to the server 901.

In the following cases, the client device 902 may issue a request for transmitting a three-dimensional map to the server 901. When the three-dimensional map held by the client device 902 is old, the client device 902 may issue a request for transmitting the three-dimensional map to the server 901. For example, when a certain period has elapsed since the client device 902 acquired the three-dimensional map, the client device 902 may issue a request for transmitting the three-dimensional map to the server 901.

The client device 902 may issue a request for transmitting the three-dimensional map to the server 901 before a certain time before the client device 902 goes out of the space indicated by the three-dimensional map held by the client device 902. For example, when the client device 902 exists within a predetermined distance from the boundary of the space indicated by the three-dimensional map held by the client device 902, the client device 902 issues a transmission request of the three-dimensional map to the server 901. May be. When the moving route and the moving speed of the client device 902 are known, the time at which the client device 902 goes out is predicted from the space indicated by the three-dimensional map held by the client device 902 based on these. May be.

(4) The client device 902 may issue a request for transmitting the three-dimensional map to the server 901 when the error at the time of alignment between the three-dimensional data created by the client device 902 from the sensor information and the three-dimensional map is equal to or more than a certain value.

The client device 902 transmits the sensor information to the server 901 in response to the transmission request of the sensor information transmitted from the server 901. Note that the client device 902 may transmit the sensor information to the server 901 without waiting for the request for transmitting the sensor information from the server 901. For example, when the client device 902 once receives a request for transmitting sensor information from the server 901, the client device 902 may periodically transmit the sensor information to the server 901 for a certain period. In addition, when the error at the time of alignment between the three-dimensional data created by the client device 902 based on the sensor information and the three-dimensional map obtained from the server 901 is equal to or more than a certain value, the client device 902 It may be determined that a change has occurred in the three-dimensional map, and the fact and the sensor information may be transmitted to the server 901.

The server 901 issues a request for transmitting sensor information to the client device 902. For example, the server 901 receives position information of the client device 902 such as GPS from the client device 902. If the server 901 determines that the client device 902 is approaching a space with less information in the three-dimensional map managed by the server 901 based on the position information of the client device 902, the client 901 generates a new three-dimensional map in order to generate a new three-dimensional map. A request for transmitting sensor information is issued to the device 902. Also, the server 901 issues a sensor information transmission request when updating the three-dimensional map, when checking the road conditions such as snowfall or disaster, when checking the traffic congestion status, or the accident / accident status. Is also good.

The client device 902 may set the data amount of the sensor information to be transmitted to the server 901 according to the communication state or the band at the time of receiving the transmission request of the sensor information received from the server 901. Setting the data amount of the sensor information to be transmitted to the server 901 means, for example, increasing or decreasing the data itself or appropriately selecting a compression method.

FIG. 29 is a block diagram showing a configuration example of the client device 902. The client device 902 receives a three-dimensional map composed of a point cloud or the like from the server 901 and estimates the self-position of the client device 902 from three-dimensional data created based on sensor information of the client device 902. Further, the client device 902 transmits the acquired sensor information to the server 901.

The client device 902 includes a data receiving unit 1011, a communication unit 1012, a reception control unit 1013, a format conversion unit 1014, a plurality of sensors 1015, a three-dimensional data creation unit 1016, a three-dimensional image processing unit 1017, It includes a three-dimensional data storage unit 1018, a format conversion unit 1019, a communication unit 1020, a transmission control unit 1021, and a data transmission unit 1022.

The data receiving unit 1011 receives the three-dimensional map 1031 from the server 901. The three-dimensional map 1031 is data including a point cloud such as WLD or SWLD. The three-dimensional map 1031 may include either compressed data or uncompressed data.

The communication unit 1012 communicates with the server 901, and transmits a data transmission request (for example, a transmission request of a three-dimensional map) to the server 901.

(4) The reception control unit 1013 exchanges information such as a compatible format with a communication destination via the communication unit 1012, and establishes communication with the communication destination.

The format conversion unit 1014 generates a three-dimensional map 1032 by performing format conversion or the like on the three-dimensional map 1031 received by the data reception unit 1011. When the three-dimensional map 1031 is compressed or encoded, the format conversion unit 1014 performs decompression or decoding. If the three-dimensional map 1031 is uncompressed data, the format conversion unit 1014 does not perform the decompression or decoding processing.

The plurality of sensors 1015 are a group of sensors, such as a LiDAR, a visible light camera, an infrared camera, and a depth sensor, that acquire information outside the vehicle in which the client device 902 is mounted, and generate the sensor information 1033. For example, when the sensor 1015 is a laser sensor such as LiDAR, the sensor information 1033 is three-dimensional data such as a point cloud (point cloud data). The number of the sensors 1015 may not be plural.

The three-dimensional data creation unit 1016 creates three-dimensional data 1034 around the own vehicle based on the sensor information 1033. For example, the three-dimensional data creation unit 1016 creates point cloud data with color information around the own vehicle using information acquired by LiDAR and a visible light image obtained by a visible light camera.

The three-dimensional image processing unit 1017 performs a self-position estimation process of the own vehicle using the received three-dimensional map 1032 such as a point cloud and the three-dimensional data 1034 around the own vehicle generated from the sensor information 1033. . The three-dimensional image processing unit 1017 creates the three-dimensional data 1035 around the own vehicle by combining the three-dimensional map 1032 and the three-dimensional data 1034, and estimates the self-position using the created three-dimensional data 1035. Processing may be performed.

The three-dimensional data storage unit 1018 stores the three-dimensional map 1032, the three-dimensional data 1034, the three-dimensional data 1035, and the like.

The format conversion unit 1019 generates the sensor information 1037 by converting the sensor information 1033 into a format supported by the receiving side. Note that the format conversion unit 1019 may reduce the data amount by compressing or encoding the sensor information 1037. Further, the format conversion unit 1019 may omit the processing when it is not necessary to perform the format conversion. Further, the format conversion unit 1019 may control the amount of data to be transmitted according to the designation of the transmission range.

The communication unit 1020 communicates with the server 901 and receives a data transmission request (a request for transmitting sensor information) and the like from the server 901.

The transmission control unit 1021 exchanges information such as a compatible format with a communication destination via the communication unit 1020 to establish communication.

The data transmission unit 1022 transmits the sensor information 1037 to the server 901. The sensor information 1037 includes a plurality of sensors such as information acquired by LiDAR, a luminance image acquired by a visible light camera, an infrared image acquired by an infrared camera, a depth image acquired by a depth sensor, sensor position information, and speed information. 1015 includes the information acquired.

Next, the configuration of the server 901 will be described. FIG. 30 is a block diagram illustrating a configuration example of the server 901. The server 901 receives the sensor information transmitted from the client device 902, and creates three-dimensional data based on the received sensor information. The server 901 updates the three-dimensional map managed by the server 901 using the created three-dimensional data. In addition, the server 901 transmits the updated three-dimensional map to the client device 902 in response to the transmission request of the three-dimensional map from the client device 902.

The server 901 includes a data reception unit 1111, a communication unit 1112, a reception control unit 1113, a format conversion unit 1114, a three-dimensional data creation unit 1116, a three-dimensional data synthesis unit 1117, and a three-dimensional data storage unit 1118. , A format conversion unit 1119, a communication unit 1120, a transmission control unit 1121, and a data transmission unit 1122.

The data receiving unit 1111 receives the sensor information 1037 from the client device 902. The sensor information 1037 includes, for example, information acquired by LiDAR, a luminance image acquired by a visible light camera, an infrared image acquired by an infrared camera, a depth image acquired by a depth sensor, sensor position information, speed information, and the like.

The communication unit 1112 communicates with the client device 902, and transmits a data transmission request (for example, a request for transmitting sensor information) to the client device 902.

The reception control unit 1113 exchanges information such as a compatible format with a communication destination via the communication unit 1112 to establish communication.

When the received sensor information 1037 is compressed or encoded, the format conversion unit 1114 generates the sensor information 1132 by performing expansion or decoding. If the sensor information 1037 is non-compressed data, the format conversion unit 1114 does not perform the decompression or decoding processing.

The three-dimensional data creation unit 1116 creates three-dimensional data 1134 around the client device 902 based on the sensor information 1132. For example, the three-dimensional data creation unit 1116 creates point cloud data with color information around the client device 902 using information acquired by LiDAR and a visible light image obtained by a visible light camera.

The three-dimensional data combining unit 1117 updates the three-dimensional map 1135 by combining the three-dimensional data 1134 created based on the sensor information 1132 with the three-dimensional map 1135 managed by the server 901.

(3) The three-dimensional data storage unit 1118 stores the three-dimensional map 1135 and the like.

The format conversion unit 1119 generates the three-dimensional map 1031 by converting the three-dimensional map 1135 into a format supported by the receiving side. Note that the format conversion unit 1119 may reduce the data amount by compressing or encoding the three-dimensional map 1135. Further, the format conversion section 1119 may omit the processing when the format conversion is not necessary. Further, the format conversion section 1119 may control the amount of data to be transmitted according to the designation of the transmission range.

The communication unit 1120 communicates with the client device 902 and receives a data transmission request (a request for transmitting a three-dimensional map) from the client device 902.

The transmission control unit 1121 exchanges information such as a compatible format with a communication destination via the communication unit 1120 to establish communication.

The data transmission unit 1122 transmits the three-dimensional map 1031 to the client device 902. The three-dimensional map 1031 is data including a point cloud such as WLD or SWLD. The three-dimensional map 1031 may include either compressed data or uncompressed data.

Next, an operation flow of the client device 902 will be described. FIG. 31 is a flowchart illustrating an operation when the client device 902 acquires a three-dimensional map.

First, the client device 902 requests the server 901 to transmit a three-dimensional map (point cloud or the like) (S1001). At this time, the client device 902 may request the server 901 to transmit a three-dimensional map related to the position information by transmitting the position information of the client device 902 obtained by GPS or the like together.

Next, the client device 902 receives the three-dimensional map from the server 901 (S1002). If the received three-dimensional map is compressed data, the client device 902 decodes the received three-dimensional map to generate an uncompressed three-dimensional map (S1003).

Next, the client device 902 creates three-dimensional data 1034 around the client device 902 from the sensor information 1033 obtained by the plurality of sensors 1015 (S1004). Next, the client device 902 estimates the self-position of the client device 902 using the three-dimensional map 1032 received from the server 901 and the three-dimensional data 1034 created from the sensor information 1033 (S1005).

FIG. 32 is a flowchart showing the operation of the client device 902 when transmitting sensor information. First, the client device 902 receives a request for transmitting sensor information from the server 901 (S1011). The client device 902 that has received the transmission request transmits the sensor information 1037 to the server 901 (S1012). Note that when the sensor information 1033 includes a plurality of pieces of information obtained by the plurality of sensors 1015, the client apparatus 902 generates the sensor information 1037 by compressing each piece of information by a compression method suitable for each piece of information. Good.

Next, the operation flow of the server 901 will be described. FIG. 33 is a flowchart illustrating the operation of the server 901 when acquiring sensor information. First, the server 901 requests the client device 902 to transmit sensor information (S1021). Next, the server 901 receives the sensor information 1037 transmitted from the client device 902 in response to the request (S1022). Next, the server 901 creates three-dimensional data 1134 using the received sensor information 1037 (S1023). Next, the server 901 reflects the created three-dimensional data 1134 on the three-dimensional map 1135 (S1024).

FIG. 34 is a flowchart showing the operation of the server 901 when transmitting a three-dimensional map. First, the server 901 receives a request for transmitting a three-dimensional map from the client device 902 (S1031). The server 901 that has received the request for transmitting the three-dimensional map transmits the three-dimensional map 1031 to the client device 902 (S1032). At this time, the server 901 may extract a nearby three-dimensional map in accordance with the position information of the client device 902 and transmit the extracted three-dimensional map. In addition, the server 901 may compress the three-dimensional map configured by the point cloud using, for example, a compression method using an octree structure and transmit the compressed three-dimensional map.

Hereinafter, a modified example of the present embodiment will be described.

The server 901 creates the three-dimensional data 1134 near the position of the client device 902 using the sensor information 1037 received from the client device 902. Next, the server 901 calculates a difference between the three-dimensional data 1134 and the three-dimensional map 1135 by matching the created three-dimensional data 1134 with a three-dimensional map 1135 in the same area managed by the server 901. . If the difference is equal to or larger than a predetermined threshold, the server 901 determines that some abnormality has occurred around the client device 902. For example, when land subsidence occurs due to a natural disaster such as an earthquake, a large difference occurs between the three-dimensional map 1135 managed by the server 901 and the three-dimensional data 1134 created based on the sensor information 1037. It is possible.

The sensor information 1037 may include information indicating at least one of a sensor type, a sensor performance, and a sensor model number. Further, a class ID or the like according to the performance of the sensor may be added to the sensor information 1037. For example, when the sensor information 1037 is information acquired by LiDAR, a sensor capable of acquiring information with an accuracy of several mm units is Class 1, a sensor capable of acquiring information with an accuracy of several cm units is Class 2, and a sensor capable of acquiring information with an accuracy of several m units. It is conceivable to assign an identifier to the performance of the sensor, such as class 3, for a sensor capable of acquiring information with accuracy. Further, the server 901 may estimate the performance information of the sensor or the like from the model number of the client device 902. For example, when the client device 902 is mounted on a vehicle, the server 901 may determine the sensor specification information from the vehicle type of the vehicle. In this case, the server 901 may have acquired the information of the type of the vehicle in advance, or the sensor information may include the information. The server 901 may use the acquired sensor information 1037 to switch the degree of correction for the three-dimensional data 1134 created using the sensor information 1037. For example, when the sensor performance is high accuracy (class 1), the server 901 does not perform correction on the three-dimensional data 1134. When the sensor performance is low accuracy (class 3), the server 901 applies a correction to the three-dimensional data 1134 according to the accuracy of the sensor. For example, the server 901 increases the degree of correction (intensity) as the accuracy of the sensor is lower.

The server 901 may simultaneously issue a request for transmitting sensor information to a plurality of client devices 902 in a certain space. When the server 901 receives a plurality of sensor information from a plurality of client devices 902, it is not necessary to use all the sensor information for creating the three-dimensional data 1134. For example, the server 901 uses the sensor information according to the performance of the sensor. Information may be selected. For example, when updating the three-dimensional map 1135, the server 901 selects high-precision sensor information (class 1) from a plurality of pieces of received sensor information, and creates three-dimensional data 1134 using the selected sensor information. May be.

The server 901 is not limited to a server such as a traffic monitoring cloud, but may be another client device (vehicle). FIG. 35 is a diagram showing a system configuration in this case.

For example, the client device 902C issues a sensor information transmission request to the nearby client device 902A, and acquires the sensor information from the client device 902A. Then, the client device 902C creates three-dimensional data using the acquired sensor information of the client device 902A, and updates the three-dimensional map of the client device 902C. Accordingly, the client device 902C can generate a three-dimensional map of a space that can be acquired from the client device 902A by utilizing the performance of the client device 902C. For example, it is considered that such a case occurs when the performance of the client device 902C is high.

In this case, the client device 902A that has provided the sensor information is given a right to acquire a highly accurate three-dimensional map generated by the client device 902C. The client device 902A receives a high-precision three-dimensional map from the client device 902C according to the right.

The client device 902C may issue a sensor information transmission request to a plurality of nearby client devices 902 (client device 902A and client device 902B). When the sensor of the

client device

902A or 902B has high performance, the client device 902C can create three-dimensional data using the sensor information obtained by the high performance sensor.

FIG. 36 is a block diagram showing a functional configuration of the server 901 and the client device 902. The server 901 includes, for example, a three-dimensional map compression / decoding processing unit 1201 that compresses and decodes a three-dimensional map, and a sensor information compression / decoding processing unit 1202 that compresses and decodes sensor information.

The client device 902 includes a three-dimensional map decoding processing unit 1211 and a sensor information compression processing unit 1212. The three-dimensional map decoding unit 1211 receives the encoded data of the compressed three-dimensional map, and decodes the encoded data to obtain a three-dimensional map. The sensor information compression processing unit 1212 compresses the sensor information itself instead of the three-dimensional data created from the acquired sensor information, and transmits the encoded data of the compressed sensor information to the server 901. With this configuration, the client device 902 only needs to internally store a processing unit (device or LSI) that performs processing for decoding a three-dimensional map (point cloud or the like). There is no need to internally store a processing unit that performs a process of compressing the data. Thus, the cost and power consumption of the client device 902 can be reduced.

As described above, the client device 902 according to the present embodiment is mounted on the mobile object, and the sensor information 1033 indicating the surrounding state of the mobile object obtained by the sensor 1015 mounted on the mobile object. The surrounding three-dimensional data 1034 is created. The client device 902 estimates the self-position of the moving object using the created three-dimensional data 1034. The client device 902 transmits the acquired sensor information 1033 to the server 901 or another moving object 902.

According to this, the client device 902 transmits the sensor information 1033 to the server 901 or the like. Thus, there is a possibility that the data amount of the transmission data can be reduced as compared with the case where the three-dimensional data is transmitted. Further, since there is no need to perform processing such as compression or encoding of three-dimensional data in the client device 902, the processing amount of the client device 902 can be reduced. Therefore, the client device 902 can reduce the amount of data to be transmitted or simplify the configuration of the device.

{Circle around (2)} The client device 902 further transmits a request for transmitting a three-dimensional map to the server 901, and receives the three-dimensional map 1031 from the server 901. In estimating the self-position, the client device 902 estimates the self-position using the three-dimensional data 1034 and the three-dimensional map 1032.

The sensor information 1033 includes at least one of information obtained by the laser sensor, a luminance image, an infrared image, a depth image, sensor position information, and sensor speed information.

(4) The sensor information 1033 includes information indicating the performance of the sensor.

The client device 902 encodes or compresses the sensor information 1033, and transmits the encoded or compressed sensor information 1037 to the server 901 or another mobile unit 902 in transmitting the sensor information. According to this, the client device 902 can reduce the amount of data to be transmitted.

{For example, the client device 902 includes a processor and a memory, and the processor performs the above processing using the memory.

In addition, server 901 according to the present embodiment can communicate with client device 902 mounted on the moving object, and sensor information 1037 indicating the surrounding state of the moving object obtained by sensor 1015 mounted on the moving object. Is received from the client device 902. The server 901 creates three-dimensional data 1134 around the moving object from the received sensor information 1037.

According to this, the server 901 creates the three-dimensional data 1134 using the sensor information 1037 transmitted from the client device 902. Thereby, there is a possibility that the data amount of the transmission data can be reduced as compared with the case where the client device 902 transmits the three-dimensional data. Further, since there is no need to perform processing such as compression or encoding of three-dimensional data in the client device 902, the processing amount of the client device 902 can be reduced. Therefore, the server 901 can reduce the amount of data to be transmitted or simplify the configuration of the device.

{Circle around (1)} Further, the server 901 transmits a request for transmitting sensor information to the client device 902.

The server 901 further updates the three-dimensional map 1135 using the created three-dimensional data 1134, and sends the three-dimensional map 1135 to the client device 902 in response to a transmission request of the three-dimensional map 1135 from the client device 902. Send.

The sensor information 1037 includes at least one of information obtained by the laser sensor, a luminance image, an infrared image, a depth image, sensor position information, and sensor speed information.

(4) The sensor information 1037 includes information indicating the performance of the sensor.

(5) The server 901 further corrects the three-dimensional data according to the performance of the sensor. According to this, the three-dimensional data creation method can improve the quality of three-dimensional data.

Further, when receiving the sensor information, the server 901 receives the plurality of sensor information 1037 from the plurality of client devices 902, and based on the plurality of information indicating the sensor performance included in the plurality of sensor information 1037, the three-dimensional data 1134. Of sensor information 1037 to be used for the creation of. According to this, the server 901 can improve the quality of the three-dimensional data 1134.

{Circle around (7)} The server 901 decodes or expands the received sensor information 1037, and creates three-dimensional data 1134 from the decoded or expanded sensor information 1132. According to this, the server 901 can reduce the amount of data to be transmitted.

For example, the server 901 includes a processor and a memory, and the processor performs the above-described processing using the memory.

(Embodiment 7)
In the present embodiment, an encoding method and a decoding method of three-dimensional data using inter prediction processing will be described.

FIG. 37 is a block diagram of a three-dimensional data encoding device 1300 according to the present embodiment. The three-dimensional data encoding device 1300 generates an encoded bit stream (hereinafter, also simply referred to as a bit stream) as an encoded signal by encoding the three-dimensional data. As shown in FIG. 37, the three-dimensional data encoding device 1300 includes a dividing unit 1301, a subtracting unit 1302, a transforming unit 1303, a quantizing unit 1304, an inverse quantizing unit 1305, and an inverse transforming unit 1306. An adder 1307, a reference volume memory 1308, an intra predictor 1309, a reference space memory 1310, an inter predictor 1311, a prediction controller 1312, and an entropy encoder 1313 are provided.

The division unit 1301 divides each space (SPC) included in the three-dimensional data into a plurality of volumes (VLM) which are coding units. Further, the dividing unit 1301 expresses voxels in each volume in an octree (octree). The dividing unit 1301 may make the space and the volume the same size, and express the space in an octree. In addition, the dividing unit 1301 may add information (depth information and the like) necessary for octanting to a bit stream header or the like.

The subtraction unit 1302 calculates a difference between the volume (encoding target volume) output from the division unit 1301 and a prediction volume generated by intra prediction or inter prediction described later, and uses the calculated difference as a prediction residual. Output to conversion section 1303. FIG. 38 is a diagram illustrating a calculation example of the prediction residual. The bit strings of the encoding target volume and the prediction volume shown here are, for example, position information indicating the positions of three-dimensional points (for example, point clouds) included in the volume.

Hereinafter, the octree expression and the voxel scanning order will be described. The volume is converted into an octree structure (octaring) and then encoded. The octree structure is composed of nodes and leaves. Each node has eight nodes or leaves, and each leaf has voxel (VXL) information. FIG. 39 is a diagram illustrating a configuration example of a volume including a plurality of voxels. FIG. 40 is a diagram showing an example in which the volume shown in FIG. 39 is converted into an octree structure. Here, among the leaves shown in FIG. 40, leaves 1, 2, and 3 represent the voxels VXL1, VXL2, and VXL3 shown in FIG. 39, respectively, and represent VXL including a point group (hereinafter, effective VXL).

The 8-ary tree is represented by, for example, a binary sequence of 0 and 1. For example, assuming that a node or a valid VXL has a value of 1 and other values have a value of 0, a binary sequence shown in FIG. 40 is assigned to each node and leaf. The binary sequence is scanned according to the width-first or depth-first scanning order. For example, when scanning is performed with breadth first, a binary sequence shown in FIG. 41A is obtained. When scanning is performed with depth priority, a binary sequence shown in FIG. 41B is obtained. The binary sequence obtained by this scan is encoded by entropy encoding to reduce the amount of information.

Next, the depth information in the octree description will be described. The depth in the octree representation is used to control to what granularity point cloud information contained in the volume is retained. If the depth is set to be large, the point cloud information can be reproduced to a finer level, but the amount of data for expressing nodes and leaves increases. Conversely, if the depth is set to a small value, the data amount will decrease, but the point cloud information having different positions and different colors will be regarded as the same position and the same color, and the information possessed by the original point cloud information will be lost. become.

For example, FIG. 42 is a diagram illustrating an example in which the octree having a depth of 2 shown in FIG. 40 is represented by an octree having a depth of 1. The octree shown in FIG. 42 has a smaller data amount than the octree shown in FIG. That is, the octree shown in FIG. 42 has a smaller number of bits after binarization than the octree shown in FIG. Here, leaf 1 and leaf 2 shown in FIG. 40 are represented by leaf 1 shown in FIG. That is, the information that the leaf 1 and the leaf 2 shown in FIG. 40 are at different positions is lost.

FIG. 43 is a diagram showing volumes corresponding to the octree shown in FIG. VXL1 and VXL2 shown in FIG. 39 correspond to VXL12 shown in FIG. In this case, the three-dimensional data encoding device 1300 generates the color information of VXL12 shown in FIG. 43 from the color information of VXL1 and VXL2 shown in FIG. For example, the three-dimensional data encoding device 1300 calculates an average value, an intermediate value, or a weighted average value of the color information of VXL1 and VXL2 as the color information of VXL12. As described above, the three-dimensional data encoding device 1300 may control the reduction of the data amount by changing the depth of the octree.

The three-dimensional data encoding device 1300 may set the depth information of the octree in any of a world unit, a space unit, and a volume unit. At that time, the three-dimensional data encoding device 1300 may add depth information to world header information, space header information, or volume header information. Also, the same value may be used as depth information for all worlds, spaces, and volumes at different times. In this case, the three-dimensional data encoding device 1300 may add depth information to header information that manages the world for the entire time.

If the voxel includes color information, the conversion unit 1303 applies frequency transformation such as orthogonal transformation to the prediction residual of the color information of the voxel in the volume. For example, the conversion unit 1303 creates a one-dimensional array by scanning the prediction residuals in a certain scan order. After that, the conversion unit 1303 converts the one-dimensional array into the frequency domain by applying a one-dimensional orthogonal transform to the created one-dimensional array. As a result, when the value of the prediction residual in the volume is close, the value of the low frequency component increases, and the value of the high frequency component decreases. Therefore, the quantization unit 1304 can more efficiently reduce the code amount.

{Circle around (1)} The transform unit 1303 may use two-dimensional or more orthogonal transform instead of one-dimensional. For example, the conversion unit 1303 maps the prediction residuals to a two-dimensional array in a certain scan order, and applies a two-dimensional orthogonal transform to the obtained two-dimensional array. Further, transform section 1303 may select an orthogonal transform scheme to be used from a plurality of orthogonal transform schemes. In this case, the three-dimensional data encoding device 1300 adds information indicating which orthogonal transform method is used to the bit stream. Further, transform section 1303 may select an orthogonal transform scheme to be used from a plurality of orthogonal transform schemes having different dimensions. In this case, the three-dimensional data encoding device 1300 adds, to the bit stream, the dimension of the orthogonal transform method used.

{For example, the conversion unit 1303 matches the scan order of the prediction residual with the scan order (width-first or depth-first, etc.) in the octree in the volume. This eliminates the need to add information indicating the scan order of the prediction residual to the bit stream, thereby reducing overhead. The conversion unit 1303 may apply a scan order different from the scan order of the octree. In this case, the three-dimensional data encoding device 1300 adds information indicating the scan order of the prediction residual to the bit stream. Accordingly, the three-dimensional data encoding device 1300 can efficiently encode the prediction residual. Also, the three-dimensional data encoding apparatus 1300 adds information (such as a flag) indicating whether or not to apply the scan order of the octree to the bit stream, and performs a prediction when the scan order is not applied. Information indicating the scanning order of the residuals may be added to the bit stream.

The conversion unit 1303 may convert not only the prediction residual of the color information but also other attribute information of the voxel. For example, the conversion unit 1303 may convert and encode information such as reflectivity obtained when the point cloud is acquired by LiDAR or the like.

If the space does not have attribute information such as color information, the conversion unit 1303 may skip the process. Also, the three-dimensional data encoding device 1300 may add information (flag) indicating whether to skip the process of the conversion unit 1303 to the bitstream.

The quantization unit 1304 generates a quantization coefficient by performing quantization using the quantization control parameter on the frequency component of the prediction residual generated by the conversion unit 1303. This reduces the amount of information. The generated quantized coefficient is output to entropy coding section 1313. The quantization unit 1304 may control the quantization control parameter in world units, space units, or volume units. At that time, the three-dimensional data encoding device 1300 adds a quantization control parameter to each header information or the like. In addition, the quantization unit 1304 may perform quantization control by changing the weight for each frequency component of the prediction residual. For example, the quantization unit 1304 may quantize low-frequency components finely and quantize high-frequency components roughly. In this case, the three-dimensional data encoding device 1300 may add a parameter indicating the weight of each frequency component to the header.

If the space has no attribute information such as color information, the quantization unit 1304 may skip the process. Also, the three-dimensional data encoding device 1300 may add information (flag) indicating whether to skip the process of the quantization unit 1304 to the bitstream.

The inverse quantization unit 1305 performs inverse quantization on the quantization coefficient generated by the quantization unit 1304 using the quantization control parameter to generate an inverse quantization coefficient of the prediction residual, and generates the generated inverse quantum The conversion coefficient is output to the inverse transform unit 1306.

The inverse transform unit 1306 generates a prediction residual after applying the inverse transform by applying an inverse transform to the inverse quantization coefficient generated by the inverse quantization unit 1305. Since the prediction residual after applying the inverse transform is a prediction residual generated after quantization, it does not need to completely match the prediction residual output by the transform unit 1303.

The addition unit 1307 includes a prediction residual after inverse transformation applied generated by the inverse transformation unit 1306 and a prediction volume generated by intra prediction or inter prediction, which is used for generation of the prediction residual before quantization, and which will be described later. Are added to generate a reconstructed volume. This reconstructed volume is stored in the reference volume memory 1308 or the reference space memory 1310.

The intra prediction unit 1309 generates a predicted volume of the encoding target volume using the attribute information of the adjacent volume stored in the reference volume memory 1308. The attribute information includes voxel color information or reflectivity. The intra prediction unit 1309 generates color information of the encoding target volume or a predicted value of the reflectance.

FIG. 44 is a diagram illustrating the operation of intra prediction section 1309. For example, the intra prediction unit 1309 generates the prediction volume of the encoding target volume (volume idx = 3) shown in FIG. 44 from the adjacent volume (volume idx = 0). Here, the volume idx is identifier information added to the volume in the space, and a different value is assigned to each volume. The allocation order of the volume idx may be the same order as the coding order, or may be a different order from the coding order. For example, the intra prediction unit 1309 uses the average value of the color information of voxels included in the volume idx = 0, which is the adjacent volume, as the predicted value of the color information of the encoding target volume shown in FIG. In this case, a prediction residual is generated by subtracting the predicted value of the color information from the color information of each voxel included in the encoding target volume. The processing after the conversion unit 1303 is performed on the prediction residual. Also, in this case, the three-dimensional data encoding device 1300 adds the adjacent volume information and the prediction mode information to the bit stream. Here, the adjacent volume information is information indicating an adjacent volume used for prediction, for example, a volume idx of the adjacent volume used for prediction. The prediction mode information indicates a mode used for generating a prediction volume. The mode is, for example, an average mode in which a predicted value is generated from an average value of voxels in an adjacent volume, an intermediate value mode in which a predicted value is generated from an intermediate value of voxels in an adjacent volume, or the like.

The intra prediction unit 1309 may generate a prediction volume from a plurality of adjacent volumes. For example, in the configuration illustrated in FIG. 44, the intra prediction unit 1309 generates the predicted volume 0 from the volume with the volume idx = 0, and generates the predicted volume 1 from the volume with the volume idx = 1. Then, the intra prediction unit 1309 generates an average of the predicted volume 0 and the predicted volume 1 as a final predicted volume. In this case, the three-dimensional data encoding device 1300 may add a plurality of volumes idx of the plurality of volumes used for generating the predicted volume to the bitstream.

FIG. 45 is a diagram schematically showing the inter prediction process according to the present embodiment. The inter prediction unit 1311 codes (inter predicts) a space (SPC) at a certain time T_Cur using a coded space at a different time T_LX. In this case, the inter prediction unit 1311 performs the encoding process by applying rotation and translation processing to the encoded space at a different time T_LX.

{Circle around (3)} The three-dimensional data encoding device 1300 adds RT information related to rotation and translation processing applied to a space at a different time T_LX to a bit stream. The different time T_LX is, for example, a time T_L0 before the certain time T_Cur. At this time, the three-dimensional data encoding device 1300 may add the RT information RT_L0 related to the rotation and translation processing applied to the space at the time T_L0 to the bit stream.

Or the different time T_LX is, for example, the time T_L1 after the certain time T_Cur. At this time, the three-dimensional data encoding device 1300 may add the RT information RT_L1 related to the rotation and translation processing applied to the space at the time T_L1 to the bit stream.

Alternatively, the inter prediction unit 1311 performs encoding (bi-prediction) with reference to both spaces at different times T_L0 and T_L1. In this case, the three-dimensional data encoding device 1300 may add both the RT information RT_L0 and RT_L1 related to rotation and translation applied to each space to the bit stream.

In the above description, T_L0 is a time before T_Cur and T_L1 is a time after T_Cur, but the present invention is not limited to this. For example, T_L0 and T_L1 may both be times before T_Cur. Alternatively, both T_L0 and T_L1 may be times after T_Cur.

Further, when encoding is performed with reference to a plurality of different time spaces, the three-dimensional data encoding device 1300 may add RT information related to rotation and translation applied to each space to the bit stream. Good. For example, the three-dimensional data encoding device 1300 manages a plurality of encoded spaces to be referred to in two reference lists (L0 list and L1 list). The first reference space in the L0 list is L0R0, the second reference space in the L0 list is L0R1, the first reference space in the L1 list is L1R0, and the second reference space in the L1 list is L1R1. In this case, the three-dimensional data encoding device 1300 adds the RT information RT_L0R0 of L0R0, the RT information RT_L0R1 of L0R1, the RT information RT_L1R0 of L1R0, and the RT information RT_L1R1 of L1R1 to the bit stream. For example, the three-dimensional data encoding device 1300 adds the RT information to a bit stream header or the like.

In addition, when encoding is performed with reference to a plurality of reference spaces at different times, the three-dimensional data encoding device 1300 determines whether to apply rotation and translation for each reference space. At that time, the three-dimensional data encoding device 1300 may add information (such as an RT application flag) indicating whether rotation and translation have been applied to each reference space to the header information of the bit stream. For example, the three-dimensional data encoding device 1300 calculates RT information and an ICP error value using an ICP (Interactive Closest Point) algorithm for each reference space referenced from the encoding target space. When the ICP error value is equal to or less than a predetermined fixed value, the three-dimensional data encoding device 1300 determines that there is no need to perform rotation and translation, and sets the RT application flag to off. On the other hand, when the ICP error value is larger than the fixed value, the three-dimensional data encoding device 1300 sets the RT application flag to ON and adds the RT information to the bit stream.

FIG. 46 is a diagram illustrating an example of a syntax for adding RT information and an RT application flag to a header. Note that the number of bits allocated to each syntax may be determined within a range that the syntax can take. For example, when the number of reference spaces included in the reference list L0 is 8, 3 bits may be allocated to MaxRefSpc_10. The number of bits to be allocated may be variable according to the value that each syntax can take, or may be fixed regardless of the value that can take. When the number of bits to be allocated is fixed, the three-dimensional data encoding device 1300 may add the fixed number of bits to another header information.

Here, MaxRefSpc_10 shown in FIG. 46 indicates the number of reference spaces included in the reference list L0. RT_flag_10 [i] is an RT application flag of the reference space i in the reference list L0. If RT_flag_10 [i] is 1, rotation and translation are applied to reference space i. If RT_flag_10 [i] is 0, no rotation and translation is applied to reference space i.

R_10 [i] and T_10 [i] are RT information of the reference space i in the reference list L0. R_10 [i] is rotation information of the reference space i in the reference list L0. The rotation information indicates the content of the applied rotation processing, and is, for example, a rotation matrix or a quaternion. T_10 [i] is translation information of the reference space i in the reference list L0. The translation information indicates the content of the applied translation processing, and is, for example, a translation vector.

MaxRefSpc — 11 indicates the number of reference spaces included in the reference list L1. RT_flag_l1 [i] is an RT application flag of the reference space i in the reference list L1. If RT_flag_11 [i] is 1, rotation and translation are applied to reference space i. If RT_flag_11 [i] is 0, no rotation and translation is applied to reference space i.

R_11 [i] and T_11 [i] are RT information of the reference space i in the reference list L1. R_11 [i] is rotation information of the reference space i in the reference list L1. The rotation information indicates the content of the applied rotation processing, and is, for example, a rotation matrix or a quaternion. T_11 [i] is translation information of the reference space i in the reference list L1. The translation information indicates the content of the applied translation processing, and is, for example, a translation vector.

The inter prediction unit 1311 generates a prediction volume of the encoding target volume using the information of the encoded reference space stored in the reference space memory 1310. As described above, before generating the prediction volume of the encoding target volume, the inter prediction unit 1311 uses the encoding target space and the reference space in order to approximate the overall positional relationship between the encoding target space and the reference space. RT information is obtained using an ICP (Interactive \ Closest \ Point) algorithm. Then, the inter prediction unit 1311 obtains a reference space B by applying rotation and translation processing to the reference space using the obtained RT information. After that, the inter prediction unit 1311 generates a prediction volume of the encoding target volume in the encoding target space using the information in the reference space B. Here, the three-dimensional data encoding device 1300 adds the RT information used to obtain the reference space B to the header information or the like of the encoding target space.

In this way, the inter prediction unit 1311 approximates the overall positional relationship between the encoding target space and the reference space by applying the rotation and translation processing to the reference space, and then uses the information on the reference space to predict the prediction volume. The accuracy of the prediction volume can be improved by generating. Further, since the prediction residual can be suppressed, the code amount can be reduced. Here, an example is shown in which ICP is performed using the encoding target space and the reference space, but the present invention is not limited to this. For example, in order to reduce the processing amount, the inter prediction unit 1311 performs ICP using at least one of the encoding target space in which the number of voxels or point clouds is thinned and the reference space in which the number of voxels or point clouds is thinned. Thus, RT information may be obtained.

Further, when the ICP error value obtained as a result of the ICP is smaller than a predetermined first threshold, that is, for example, when the positional relationship between the encoding target space and the reference space is close, the inter prediction unit 1311 It is determined that the translation process is not necessary, and the rotation and translation need not be performed. In this case, the three-dimensional data encoding device 1300 may suppress the overhead by not adding the RT information to the bit stream.

Further, when the ICP error value is larger than a predetermined second threshold value, the inter prediction unit 1311 determines that the shape change between spaces is large, and applies intra prediction to all volumes in the encoding target space. May be. Hereinafter, a space to which intra prediction is applied is referred to as an intra space. Further, the second threshold is a value larger than the first threshold. The method is not limited to the ICP, and any method may be applied as long as it is a method of obtaining RT information from two voxel sets or two point cloud sets.

Also, when attribute information such as shape or color is included in the three-dimensional data, the inter prediction unit 1311 determines, as a prediction volume of the encoding target volume in the encoding target space, for example, the encoding target volume in the reference space. Is searched for a volume whose attribute information such as shape or color is closest. This reference space is, for example, a reference space after the above-described rotation and translation processing has been performed. The inter prediction unit 1311 generates a predicted volume from the volume (reference volume) obtained by the search. FIG. 47 is a diagram for explaining the operation of generating a predicted volume. When encoding the encoding target volume (volume idx = 0) illustrated in FIG. 47 by using the inter prediction, the inter prediction unit 1311 sequentially scans the reference volume in the reference space and sets the encoding target volume and the reference volume. A volume with the smallest prediction residual that is a difference from the volume is searched for. The inter prediction unit 1311 selects a volume having the smallest prediction residual as a prediction volume. The prediction residual between the encoding target volume and the prediction volume is encoded by the processing after the conversion unit 1303. Here, the prediction residual is a difference between the attribute information of the encoding target volume and the attribute information of the prediction volume. In addition, the three-dimensional data encoding device 1300 adds the volume idx of the reference volume in the reference space referred to as the prediction volume to the bit stream header or the like.

In the example shown in FIG. 47, the reference volume of volume idx = 4 in the reference space L0R0 is selected as the predicted volume of the encoding target volume. Then, the prediction residual between the encoding target volume and the reference volume and the reference volume idx = 4 are encoded and added to the bit stream.

Although the example of generating the predicted volume of the attribute information has been described here, the same process may be performed on the predicted volume of the position information.

The prediction control unit 1312 controls whether to encode the encoding target volume using intra prediction or inter prediction. Here, a mode including the intra prediction and the inter prediction is referred to as a prediction mode. For example, the prediction control unit 1312 calculates a prediction residual when the encoding target volume is predicted by the intra prediction and a prediction residual when the encoding target volume is predicted by the inter prediction, as an evaluation value. Select a mode. The prediction control unit 1312 calculates an actual code amount by applying orthogonal transformation, quantization, and entropy coding to the prediction residual of intra prediction and the prediction residual of inter prediction, respectively. The prediction mode may be selected using the obtained code amount as an evaluation value. Also, overhead information (reference volume idx information or the like) other than the prediction residual may be added to the evaluation value. In addition, the prediction control unit 1312 may always select intra prediction when it is determined in advance that the encoding target space is to be encoded in the intra space.

The entropy coding unit 1313 generates a coded signal (coded bit stream) by performing variable-length coding on the quantization coefficient input from the quantization unit 1304. Specifically, the entropy coding unit 1313 binarizes the quantization coefficient, for example, and arithmetically codes the obtained binary signal.

Next, a three-dimensional data decoding device that decodes the encoded signal generated by the three-dimensional data encoding device 1300 will be described. FIG. 48 is a block diagram of a three-dimensional data decoding device 1400 according to the present embodiment. The three-dimensional data decoding device 1400 includes an entropy decoding unit 1401, an inverse quantization unit 1402, an inverse transformation unit 1403, an addition unit 1404, a reference volume memory 1405, an intra prediction unit 1406, and a reference space memory 1407. , An inter prediction unit 1408, and a prediction control unit 1409.

The entropy decoding unit 1401 performs variable length decoding on the coded signal (coded bit stream). For example, the entropy decoding unit 1401 arithmetically decodes the encoded signal to generate a binary signal, and generates a quantization coefficient from the generated binary signal.

The inverse quantization unit 1402 generates an inverse quantization coefficient by inversely quantizing the quantization coefficient input from the entropy decoding unit 1401 using a quantization parameter added to a bit stream or the like.

The inverse transform unit 1403 generates a prediction residual by inversely transforming the inverse quantization coefficient input from the inverse quantization unit 1402. For example, the inverse transform unit 1403 generates a prediction residual by performing inverse orthogonal transform on the inverse quantized coefficient based on information added to the bit stream.

The addition unit 1404 generates a reconstructed volume by adding the prediction residual generated by the inverse transform unit 1403 and the prediction volume generated by intra prediction or inter prediction. This reconstructed volume is output as decoded three-dimensional data and stored in the reference volume memory 1405 or the reference space memory 1407.

The intra prediction unit 1406 generates a prediction volume by intra prediction using the reference volume in the reference volume memory 1405 and information added to the bit stream. Specifically, the intra prediction unit 1406 acquires adjacent volume information (for example, volume idx) added to the bit stream and prediction mode information, and uses the adjacent volume indicated by the adjacent volume information to calculate the prediction mode information. A predicted volume is generated in the mode indicated by. The details of these processes are the same as those of the above-described process performed by the intra prediction unit 1309 except that information added to the bit stream is used.

The inter prediction unit 1408 generates a prediction volume by inter prediction using the reference space in the reference space memory 1407 and the information added to the bit stream. Specifically, the inter prediction unit 1408 applies rotation and translation processing to the reference space using the RT information for each reference space added to the bit stream, and calculates the prediction volume using the applied reference space. Generate. If the RT application flag for each reference space exists in the bitstream, the inter prediction unit 1408 applies rotation and translation processing to the reference space according to the RT application flag. The details of these processes are the same as the processes by the above-described inter prediction unit 1311 except that information added to the bit stream is used.

The prediction control unit 1409 controls whether to decode the decoding target volume using intra prediction or inter prediction. For example, the prediction control unit 1409 selects intra prediction or inter prediction according to information indicating the prediction mode to be used, which is added to the bit stream. Note that the prediction control unit 1409 may always select intra prediction when decoding of the decoding target space is performed using intra space.

Hereinafter, a modified example of the present embodiment will be described. In this embodiment, an example in which rotation and translation are applied in units of space has been described, but rotation and translation may be applied in smaller units. For example, the three-dimensional data encoding device 1300 may divide a space into subspaces and apply rotation and translation in units of subspaces. In this case, the three-dimensional data encoding device 1300 generates RT information for each subspace, and adds the generated RT information to a bit stream header or the like. Also, the three-dimensional data encoding device 1300 may apply rotation and translation on a volume basis, which is an encoding unit. In this case, the three-dimensional data encoding device 1300 generates RT information for each encoded volume, and adds the generated RT information to a bit stream header or the like. Further, the above may be combined. That is, the three-dimensional data encoding device 1300 may apply rotation and translation in large units, and then apply rotation and translation in small units. For example, the three-dimensional data encoding device 1300 may apply rotation and translation in units of space, and apply different rotation and translation to each of a plurality of volumes included in the obtained space.

In the present embodiment, an example in which rotation and translation are applied to the reference space has been described, but the present invention is not necessarily limited to this. For example, the three-dimensional data encoding device 1300 may change the size of the three-dimensional data by applying a scaling process, for example. In addition, the three-dimensional data encoding device 1300 may apply one or two of rotation, translation, and scale. Further, when processing is applied in different units in multiple stages as described above, the type of processing applied to each unit may be different. For example, rotation and translation may be applied in units of space, and translation may be applied in units of volume.

Note that these modifications can be similarly applied to the three-dimensional data decoding device 1400.

As described above, the three-dimensional data encoding device 1300 according to the present embodiment performs the following processing. FIG. 48 is a flowchart of the inter prediction process performed by the three-dimensional data encoding device 1300.

First, the three-dimensional data encoding device 1300 uses the three-dimensional point position information included in the reference three-dimensional data (for example, the reference space) at a different time from the target three-dimensional data (for example, the encoding target space) for predictive position information. (For example, a predicted volume) is generated (S1301). Specifically, the three-dimensional data encoding device 1300 generates predicted position information by applying rotation and translation processing to position information of three-dimensional points included in the reference three-dimensional data.

Note that the three-dimensional data encoding device 1300 performs rotation and translation processing in a first unit (for example, space), and generates predicted position information in a second unit (for example, volume) that is finer than the first unit. Is also good. For example, the three-dimensional data encoding device 1300 determines, from among a plurality of volumes included in the reference space after the rotation and translation processing, a volume in which the difference between the position information and the encoding target volume included in the encoding target space is the smallest. The searched volume is used as a predicted volume. Note that the three-dimensional data encoding device 1300 may perform the rotation and translation processing and the generation of the predicted position information in the same unit.

Further, the three-dimensional data encoding device 1300 applies the first rotation and translation processing to the position information of the three-dimensional point included in the reference three-dimensional data in a first unit (for example, space), and performs the first rotation and translation processing. Predicted position information may be generated by applying the second rotation and translation processing to the three-dimensional point position information obtained by the above in a second unit (for example, volume) finer than the first unit.

Here, the position information and the predicted position information of the three-dimensional point are represented by an octree structure, for example, as shown in FIG. For example, the position information and the predicted position information of the three-dimensional point are expressed in the order of scanning with priority given to the width of the depth and the width in the octree structure. Alternatively, the position information and the predicted position information of the three-dimensional point are represented in a scan order in which the depth is prioritized among the depth and the width in the octree structure.

Further, as shown in FIG. 46, the three-dimensional data encoding device 1300 encodes an RT application flag indicating whether to apply rotation and translation processing to the position information of the three-dimensional point included in the reference three-dimensional data. I do. That is, the three-dimensional data encoding device 1300 generates an encoded signal (encoded bit stream) including the RT application flag. Also, the three-dimensional data encoding device 1300 encodes RT information indicating the contents of the rotation and translation processing. That is, the three-dimensional data encoding device 1300 generates an encoded signal (encoded bit stream) including the RT information. Note that the three-dimensional data encoding device 1300 encodes the RT information when the RT application flag indicates that the rotation and translation processing is to be applied, and when the RT application flag indicates that the rotation and translation processing is not to be applied. The RT information need not be coded.

(3) The three-dimensional data includes, for example, position information of three-dimensional points and attribute information (color information and the like) of each three-dimensional point. The three-dimensional data encoding device 1300 generates prediction attribute information using the attribute information of the three-dimensional point included in the reference three-dimensional data (S1302).

Next, the three-dimensional data encoding device 1300 encodes the three-dimensional point position information included in the target three-dimensional data using the predicted position information. For example, as illustrated in FIG. 38, the three-dimensional data encoding device 1300 calculates difference position information that is a difference between the position information of the three-dimensional point included in the target three-dimensional data and the predicted position information (S1303).

{3} Also, the three-dimensional data encoding device 1300 encodes attribute information of a three-dimensional point included in the target three-dimensional data using predicted attribute information. For example, the three-dimensional data encoding device 1300 calculates difference attribute information that is a difference between the attribute information of the three-dimensional point included in the target three-dimensional data and the predicted attribute information (S1304). Next, the three-dimensional data encoding device 1300 performs conversion and quantization on the calculated difference attribute information (S1305).

Finally, the three-dimensional data encoding device 1300 encodes (eg, entropy-encodes) the difference position information and the quantized difference attribute information (S1306). That is, the three-dimensional data encoding device 1300 generates an encoded signal (encoded bit stream) including the difference position information and the difference attribute information.

If the attribute information is not included in the three-dimensional data, the three-dimensional data encoding device 1300 may not perform steps S1302, S1304, and S1305. In addition, the three-dimensional data encoding device 1300 may perform only one of encoding of the position information of the three-dimensional point and encoding of the attribute information of the three-dimensional point.

The order of the processing shown in FIG. 49 is an example, and the present invention is not limited to this. For example, the processing for the position information (S1301, S1303) and the processing for the attribute information (S1302, S1304, S1305) are independent of each other, and may be performed in an arbitrary order, or may be partially performed in parallel. You may.

As described above, in the present embodiment, the three-dimensional data encoding device 1300 generates the predicted position information using the position information of the three-dimensional point included in the reference three-dimensional data at a different time from the target three-dimensional data, The difference position information that is the difference between the position information of the three-dimensional point included in the original data and the predicted position information is encoded. As a result, the data amount of the encoded signal can be reduced, so that the encoding efficiency can be improved.

Also, in the present embodiment, the three-dimensional data encoding device 1300 generates prediction attribute information using the attribute information of the three-dimensional point included in the reference three-dimensional data, and generates the prediction attribute information of the three-dimensional point included in the target three-dimensional data. The difference attribute information that is the difference between the attribute information and the predicted attribute information is encoded. As a result, the data amount of the encoded signal can be reduced, so that the encoding efficiency can be improved.

For example, the three-dimensional data encoding device 1300 includes a processor and a memory, and the processor performs the above-described processing using the memory.

FIG. 48 is a flowchart of an inter prediction process performed by the three-dimensional data decoding device 1400.

First, the three-dimensional data decoding device 1400 decodes difference position information and difference attribute information (for example, entropy decoding) from a coded signal (coded bit stream) (S1401).

{Circle around (3)} The three-dimensional data decoding device 1400 decodes, from the encoded signal, an RT application flag indicating whether to apply the rotation and translation processing to the position information of the three-dimensional point included in the reference three-dimensional data. Also, the three-dimensional data decoding device 1400 decodes RT information indicating the contents of the rotation and translation processing. Note that the three-dimensional data decoding apparatus 1400 decodes the RT information when the RT application flag indicates that the rotation and translation processing is to be applied, and when the RT application flag indicates that the rotation and translation processing is not to be applied. The RT information need not be decoded.

Next, the three-dimensional data decoding device 1400 performs inverse quantization and inverse transform on the decoded difference attribute information (S1402).

Next, the three-dimensional data decoding device 1400 uses the position information of the three-dimensional point included in the reference three-dimensional data (for example, the reference space) at a different time from the target three-dimensional data (for example, the decoding target space) to use the predicted position information ( For example, a predicted volume is generated (S1403). Specifically, the three-dimensional data decoding device 1400 generates predicted position information by applying rotation and translation processing to position information of three-dimensional points included in reference three-dimensional data.

More specifically, when the RT application flag indicates that the rotation and translation processing is to be applied, the three-dimensional data decoding apparatus 1400 determines the position information of the three-dimensional point included in the reference three-dimensional data indicated by the RT information. Apply rotation and translation processing to. On the other hand, when the RT application flag indicates that the rotation and translation processing is not to be applied, the three-dimensional data decoding device 1400 does not apply the rotation and translation processing to the position information of the three-dimensional point included in the reference three-dimensional data. .

Note that the three-dimensional data decoding apparatus 1400 may perform the rotation and translation processing in a first unit (for example, space) and generate the predicted position information in a second unit (for example, volume) that is finer than the first unit. Good. Note that the three-dimensional data decoding apparatus 1400 may perform the rotation and translation processing and the generation of the predicted position information in the same unit.

Also, the three-dimensional data decoding device 1400 applies the first rotation and translation processing to the three-dimensional point position information included in the reference three-dimensional data in a first unit (for example, space), and performs the first rotation and translation processing. Predicted position information may be generated by applying the second rotation and translation processing to the obtained three-dimensional point position information in a second unit (for example, a volume) smaller than the first unit.

The three-dimensional data decoding device 1400 generates prediction attribute information using the attribute information of the three-dimensional point included in the reference three-dimensional data (S1404).

Next, the three-dimensional data decoding device 1400 restores the three-dimensional point position information included in the target three-dimensional data by decoding the encoded position information included in the encoded signal using the predicted position information. Here, the encoded position information is, for example, difference position information, and the three-dimensional data decoding device 1400 adds the difference position information and the predicted position information to obtain a three-dimensional point of the target three-dimensional data. The position information is restored (S1405).

{Circle around (3)} The three-dimensional data decoding device 1400 restores the attribute information of the three-dimensional point included in the target three-dimensional data by decoding the encoding attribute information included in the encoded signal using the prediction attribute information. Here, the encoding attribute information is, for example, difference attribute information, and the three-dimensional data decoding device 1400 adds the difference attribute information and the prediction attribute information to obtain a three-dimensional point of the target three-dimensional data. The attribute information is restored (S1406).

If the attribute information is not included in the three-dimensional data, the three-dimensional data decoding device 1400 may not perform steps S1402, S1404, and S1406. Further, the three-dimensional data decoding device 1400 may perform only one of the decoding of the position information of the three-dimensional point and the decoding of the attribute information of the three-dimensional point.

The order of the processing shown in FIG. 50 is an example, and the present invention is not limited to this. For example, the processing for the position information (S1403, S1405) and the processing for the attribute information (S1402, S1404, S1406) are independent of each other, and may be performed in an arbitrary order, or may be partially performed in parallel. May be.

(Embodiment 8)
In the present embodiment, a method of controlling reference at the time of encoding an occupancy code will be described. Although the operation of the three-dimensional data encoding device will be mainly described below, the same processing may be performed in the three-dimensional data decoding device.

51 and 52 are diagrams showing a reference relationship according to the present embodiment. FIG. 51 is a diagram showing the reference relationship on an octree structure. FIG. 52 is a diagram showing the reference relationship on a spatial domain. FIG.

In the present embodiment, the three-dimensional data encoding device encodes the encoding information of a node to be encoded (hereinafter, referred to as a target node) when encoding the encoded information of the parent node (parent @ node) to which the target node belongs. The encoding information of each node is referred to. However, the encoding information of each node in another node in the same layer as the parent node (hereinafter, parent adjacent node) is not referred to. That is, the three-dimensional data encoding device sets the reference of the parent adjacent node to be disabled or disables the reference.

Note that the three-dimensional data encoding device may permit reference to the encoding information in the parent node to which the parent node belongs (hereinafter, referred to as a grandparent node). That is, the three-dimensional data encoding device may encode the encoding information of the target node with reference to the encoding information of the parent node and the grandfather node to which the target node belongs.

The encoded information is, for example, an occupancy code. When encoding the occupancy code of the target node, the three-dimensional data encoding device refers to information (hereinafter, occupation information) indicating whether or not each node in the parent node to which the target node belongs includes a point cloud. I do. In other words, the three-dimensional data encoding device refers to the occupancy code of the parent node when encoding the occupancy code of the target node. On the other hand, the three-dimensional data encoding device does not refer to the occupation information of each node in the parent adjacent node. That is, the three-dimensional data encoding device does not refer to the occupancy code of the parent adjacent node. Further, the three-dimensional data encoding device may refer to the occupation information of each node in the grandfather node. That is, the three-dimensional data encoding device may refer to the occupation information of the parent node and the parent adjacent node.

For example, when encoding the occupancy code of the target node, the three-dimensional data encoding device is used when entropy-encoding the occupancy code of the target node using the occupancy code of the parent node or grandfather node to which the target node belongs. Switch the encoding table. The details will be described later. At this time, the three-dimensional data encoding device need not refer to the occupancy code of the parent adjacent node. Thereby, when encoding the occupancy code of the target node, the three-dimensional data encoding device can appropriately switch the encoding table according to the information of the occupancy code of the parent node or the grandfather node. Efficiency can be improved. Also, the three-dimensional data encoding device can suppress the information processing of the parent adjacent node and the memory capacity for storing them by not referring to the parent adjacent node. Further, it becomes easy to scan and encode the occupancy code of each node of the octree in the order of depth priority.

Hereinafter, an example of coding table switching using the occupancy code of the parent node will be described. FIG. 53 is a diagram illustrating an example of a target node and an adjacent reference node. FIG. 54 is a diagram illustrating a relationship between a parent node and a node. FIG. 55 is a diagram illustrating an example of the occupancy code of the parent node. Here, the adjacent reference node is a node that is referred to when encoding the target node among nodes spatially adjacent to the target node. In the example shown in FIG. 53, the adjacent node is a node belonging to the same layer as the target node. Also, a node X adjacent in the x direction, a node Y adjacent in the y direction, and a node Z adjacent in the z direction of the target block are used as reference adjacent nodes. That is, one adjacent block in each of the x, y, and z directions is set as a reference adjacent block.

The node numbers shown in FIG. 54 are merely examples, and the relationship between the node numbers and the positions of the nodes is not limited to this. In FIG. 55, node 0 is assigned to lower bits and node 7 is assigned to upper bits. However, assignment may be performed in the reverse order. Further, each node may be assigned to an arbitrary bit.

(3) The three-dimensional data encoding device determines an encoding table for entropy encoding the occupancy code of the target node by, for example, the following equation.

CodingTable = (FlagX << 2) + (FlagY << 1) + (FlagZ)

Here, CodingTable indicates an encoding table for the occupancy code of the target node, and indicates any one of values 0 to 7. FlagX is occupancy information of the adjacent node X, and indicates 1 if the adjacent node X includes (occupies) a point cloud, and indicates 0 if not. FlagY is occupancy information of the adjacent node Y, and indicates 1 if the adjacent node Y includes (occupies) a point group, and indicates 0 if not. FlagZ is occupancy information of the adjacent node Z, and indicates 1 if the adjacent node Z includes (occupies) a point group, and indicates 0 if not.

Since the information indicating whether or not the adjacent node is occupied is included in the occupancy code of the parent node, the three-dimensional data encoding device encodes the information using the value indicated in the occupancy code of the parent node. May be selected.

As described above, the three-dimensional data encoding device can improve the encoding efficiency by switching the encoding table using information indicating whether or not a point cloud is included in a node adjacent to the target node.

(5) The three-dimensional data encoding device may switch adjacent reference nodes according to the spatial position of the target node in the parent node, as shown in FIG. That is, the three-dimensional data encoding device may switch the adjacent node to be referred to among the plurality of adjacent nodes according to the spatial position in the parent node of the target node.

Next, a configuration example of the three-dimensional data encoding device and the three-dimensional data decoding device will be described. FIG. 56 is a block diagram of a three-dimensional data encoding device 2100 according to the present embodiment. The three-dimensional data encoding device 2100 illustrated in FIG. 56 includes an octtree generation unit 2101, a geometric information calculation unit 2102, an encoding table selection unit 2103, and an entropy encoding unit 2104.

The -ary tree generating unit 2101 generates, for example, an octal tree from the input three-dimensional points (point cloud), and generates an occupancy code of each node included in the octal tree. The geometric information calculation unit 2102 acquires occupation information indicating whether or not the reference node adjacent to the target node is occupied. For example, the geometric information calculation unit 2102 acquires the occupancy information of the adjacent reference node from the occupancy code of the parent node to which the target node belongs. Note that the geometric information calculation unit 2102 may switch the adjacent reference node according to the position in the parent node of the target node as shown in FIG. Also, the geometric information calculation unit 2102 does not refer to the occupation information of each node in the parent adjacent node.

The coding table selection unit 2103 selects a coding table used for entropy coding of the occupancy code of the target node using the occupation information of the adjacent reference node calculated by the geometric information calculation unit 2102. The entropy coding unit 2104 generates a bit stream by performing entropy coding on the occupancy code using the selected coding table. Note that the entropy encoding unit 2104 may add information indicating the selected encoding table to the bitstream.

FIG. 57 is a block diagram of three-dimensional data decoding device 2110 according to the present embodiment. The three-dimensional data decoding device 2110 illustrated in FIG. 57 includes an octree generation unit 2111, a geometric information calculation unit 2112, an encoding table selection unit 2113, and an entropy decoding unit 2114.

The # 8-ary tree generation unit 2111 generates an 8-ary tree of a certain space (node) using the header information of the bit stream and the like. The octree generating unit 2111 generates a large space (root node) using the size of a certain space added to the header information in the x-axis, y-axis, and z-axis directions. Eight subspaces A (nodes A0 to A7) are generated by dividing into two in the y-axis and z-axis directions, respectively, to generate an octree. Nodes A0 to A7 are set in order as target nodes.

The geometric information calculation unit 2112 acquires occupation information indicating whether or not the reference node adjacent to the target node is occupied. For example, the geometric information calculation unit 2112 acquires the occupancy information of the adjacent reference node from the occupancy code of the parent node to which the target node belongs. Note that the geometric information calculation unit 2112 may switch the adjacent reference node according to the position of the target node in the parent node, as shown in FIG. Further, the geometric information calculation unit 2112 does not refer to the occupation information of each node in the parent adjacent node.

The encoding table selection unit 2113 selects an encoding table (decoding table) used for entropy decoding of the occupancy code of the target node using the occupation information of the adjacent reference node calculated by the geometric information calculation unit 2112. The entropy decoding unit 2114 generates a three-dimensional point by entropy decoding the occupancy code using the selected encoding table. Note that the encoding table selection unit 2113 decodes and acquires the information of the selected encoding table added to the bit stream, and the entropy decoding unit 2114 uses the encoding table indicated by the acquired information. May be.

Each bit of the occupancy code (8 bits) included in the bit stream indicates whether or not the eight small spaces A (nodes A0 to A7) each include a point cloud. Further, the three-dimensional data decoding device divides the small space node A0 into eight small spaces B (nodes B0 to B7) to generate an octree, and each node of the small space B includes a point group. The occupancy code is decoded to obtain information indicating whether or not the occupancy code is to be obtained. As described above, the three-dimensional data decoding device decodes the occupancy code of each node while generating an octree from a large space to a small space.

Hereinafter, the flow of processing performed by the three-dimensional data encoding device and the three-dimensional data decoding device will be described. FIG. 58 is a flowchart of a three-dimensional data encoding process in the three-dimensional data encoding device. First, the three-dimensional data encoding device determines (defines) a space (target node) that includes a part or all of the input three-dimensional point group (S2101). Next, the three-dimensional data encoding device divides the target node into eight to generate eight small spaces (nodes) (S2102). Next, the three-dimensional data encoding device generates an occupancy code of the target node according to whether or not each node includes a point cloud (S2103).

Next, the three-dimensional data encoding device calculates (acquires) the occupancy information of the reference node adjacent to the target node from the occupancy code of the parent node of the target node (S2104). Next, the three-dimensional data encoding device selects an encoding table used for entropy encoding based on the determined occupation information of the reference node adjacent to the target node (S2105). Next, the three-dimensional data encoding device entropy-encodes the occupancy code of the target node using the selected encoding table (S2106).

Furthermore, the three-dimensional data encoding apparatus repeats the process of dividing each node into eight and encoding the occupancy code of each node until the node cannot be divided (S2107). That is, the processing of steps S2102 to S2106 is recursively repeated.

FIG. 59 is a flowchart of a three-dimensional data decoding method in the three-dimensional data decoding device. First, the three-dimensional data decoding device determines (defines) a space (target node) to be decoded using the header information of the bit stream (S2111). Next, the three-dimensional data decoding device divides the target node into eight to generate eight small spaces (nodes) (S2112). Next, the three-dimensional data decoding device calculates (acquires) the occupancy information of the reference node adjacent to the target node from the occupancy code of the parent node of the target node (S2113).

Next, the three-dimensional data decoding apparatus selects an encoding table used for entropy decoding based on the occupation information of the adjacent reference node (S2114). Next, the three-dimensional data decoding device entropy-decodes the occupancy code of the target node using the selected encoding table (S2115).

{Furthermore, the three-dimensional data decoding device repeats the process of dividing each node into eight and decoding the occupancy code of each node until the node cannot be divided (S2116). That is, the processing of steps S2112 to S2115 is recursively repeated.

Next, an example of switching between encoding tables will be described. FIG. 60 is a diagram illustrating an example of switching of the encoding tables. For example, the same context model may be applied to a plurality of occupancy codes as in an encoding table 0 shown in FIG. Also, different context models may be assigned to each occupancy code. Thereby, a context model can be assigned according to the appearance probability of the occupancy code, so that coding efficiency can be improved. Further, a context model that updates the probability table according to the appearance frequency of the occupancy code may be used. Alternatively, a context model having a fixed probability table may be used.

Hereinafter, Modification Example 1 of the present embodiment will be described. FIG. 61 is a diagram showing a reference relationship in this modification. In the above embodiment, the three-dimensional data encoding apparatus does not refer to the occupancy code of the parent adjacent node.However, whether to refer to the occupancy encoding of the parent adjacent node is switched according to a specific condition. Is also good.

For example, when performing encoding while scanning an octree with breadth priority, the three-dimensional data encoding device encodes the occupancy code of the target node with reference to the occupancy information of the node in the parent adjacent node. On the other hand, the three-dimensional data encoding device prohibits reference to the occupancy information of the node in the parent adjacent node when encoding the octree while scanning the octree with depth priority. As described above, by switching the nodes that can be referred to appropriately in accordance with the scan order (encoding order) of the nodes of the octree, it is possible to realize an improvement in encoding efficiency and a reduction in processing load.

Note that the three-dimensional data encoding device may add information such as whether the octree was encoded with breadth-first or depth-first encoding to the header of the bit stream. FIG. 62 is a diagram illustrating a syntax example of the header information in this case. Octree_scan_order shown in FIG. 62 is coding order information (coding order flag) indicating the coding order of the octree. For example, if octree_scan_order is 0, it indicates width priority, and if it is 1, it indicates depth priority. Accordingly, the three-dimensional data decoding device can know whether the bit stream has been encoded in the width priority or the depth priority by referring to the octree_scan_order, and thus can appropriately decode the bit stream.

The three-dimensional data encoding device may add information indicating whether to prohibit reference to the parent adjacent node to the header information of the bit stream. FIG. 63 is a diagram illustrating a syntax example of the header information in this case. The limit_refer_flag is prohibition switching information (prohibition switching flag) indicating whether or not reference to the parent adjacent node is prohibited. For example, if limit_refer_flag is 1, it indicates that reference to the parent adjacent node is prohibited, and if it is 0, it indicates that there is no reference restriction (reference to the parent adjacent node is permitted).

That is, the three-dimensional data encoding device determines whether to prohibit reference to the parent adjacent node, and switches whether to prohibit or permit reference to the parent adjacent node based on the result of the above determination. In addition, the three-dimensional data encoding device generates a bit stream that is a result of the above determination and includes prohibition switching information indicating whether to prohibit reference to the parent adjacent node.

Further, the three-dimensional data decoding device acquires prohibition switching information indicating whether to prohibit reference to the parent adjacent node from the bit stream, and prohibits or permits reference to the parent adjacent node based on the prohibition switching information. Switch.

により Thereby, the three-dimensional data encoding device can generate a bit stream by controlling the reference of the parent adjacent node. Further, the three-dimensional data decoding device can acquire information indicating whether reference to the parent adjacent node is prohibited from the header of the bit stream.

Also, in the present embodiment, the encoding process of the occupancy code has been described as an example of the encoding process of prohibiting the reference of the parent adjacent node, but is not necessarily limited to this. For example, the same method can be applied when encoding other information of the node of the octree. For example, the method according to the present embodiment may be applied when encoding other attribute information such as a color, a normal vector, or a reflectance added to a node. Further, a similar method can be applied when encoding a coding table or a predicted value.

Next, Modification 2 of the present embodiment will be described. In the above description, as shown in FIG. 53, an example in which three reference adjacent nodes are used has been described, but four or more reference adjacent nodes may be used. FIG. 64 is a diagram illustrating an example of a target node and a reference adjacent node.

For example, the three-dimensional data encoding device calculates an encoding table for entropy encoding the occupancy code of the target node shown in FIG.

CodingTable = (FlagX0 << 3) + (FlagX1 << 2) + (FlagY << 1) + (FlagZ)

Here, CodingTable indicates an encoding table for the occupancy code of the target node, and indicates any one of values 0 to 15. Flag XN is occupation information of the adjacent node XN (N = 0.1), and indicates 1 if the adjacent node XN includes (occupies) the point group, and indicates 0 if not. FlagY is occupancy information of the adjacent node Y, and indicates 1 if the adjacent node Y includes (occupies) a point group, and indicates 0 if not. FlagZ is occupancy information of the adjacent node Z, and indicates 1 if the adjacent node Z includes (occupies) a point group, and indicates 0 if not.

At this time, if the adjacent node, for example, the adjacent node X0 in FIG. 64 cannot be referred to (reference prohibited), the three-dimensional data encoding device sets the substitute value to 1 (occupied) or 0 (unoccupied). Any other fixed value may be used.

FIG. 65 is a diagram illustrating an example of a target node and adjacent nodes. As shown in FIG. 65, when the adjacent node cannot be referred to (reference prohibited), the occupancy information of the adjacent node may be calculated by referring to the occupancy code of the grandfather node of the target node. For example, the three-dimensional data encoding apparatus calculates FlagX0 of the above equation using the occupation information of the adjacent node G0 instead of the adjacent node X0 shown in FIG. 65, and calculates the value of the encoding table using the calculated FlagX0. You may decide. Note that the adjacent node G0 shown in FIG. 65 is an adjacent node that can determine whether or not it is occupied by the occupancy code of the grandfather node. The adjacent node X1 is an adjacent node that can determine whether or not it is occupied by the occupancy code of the parent node.

Hereinafter, Modification 3 of the present embodiment will be described. 66 and 67 are diagrams illustrating a reference relationship according to this modification. FIG. 66 is a diagram illustrating the reference relationship on an octree structure, and FIG. 67 is a diagram illustrating the reference relationship on a spatial domain. FIG.

In this modified example, the three-dimensional data encoding apparatus encodes the encoding information of the node to be encoded (hereinafter, referred to as the target node 2) when encoding the encoding information of the node in the parent node to which the target node 2 belongs. Refer to the encoding information. That is, the three-dimensional data encoding device permits reference to information (for example, occupation information) of a child node of the first node having the same parent node as the target node among the plurality of adjacent nodes. For example, when encoding the occupancy code of the target node 2 illustrated in FIG. 66, the three-dimensional data encoding device may use a node existing in the parent node to which the target node 2 belongs, for example, the occupancy of the target node illustrated in FIG. Reference sign. The occupancy code of the target node shown in FIG. 66 indicates, for example, whether or not each node in the target node adjacent to the target node 2 is occupied, as shown in FIG. Therefore, the three-dimensional data encoding device can switch the encoding table of the occupancy code of the target node 2 according to the finer shape of the target node, so that the coding efficiency can be improved.

(3) The three-dimensional data encoding device may calculate an encoding table for entropy encoding the occupancy code of the target node 2 by, for example, the following equation.

CodingTable = (FlagX1 << 5) + (FlagX2 << 4) + (FlagX3 << 3) + (FlagX4 << 2) + (FlagY << 1) + (FlagZ)

Here, CodingTable indicates an encoding table for the occupancy code of the target node 2 and indicates any one of values 0 to 63. Flag XN is occupancy information of the adjacent node XN (N = 1.4), and indicates 1 if the adjacent node XN includes (occupies) a point cloud, and indicates 0 if not. FlagY is occupancy information of the adjacent node Y, and indicates 1 if the adjacent node Y includes (occupies) a point group, and indicates 0 if not. FlagZ is occupancy information of the adjacent node Y, and indicates 1 if the adjacent node Z includes (occupies) a point group, and indicates 0 if not.

The three-dimensional data encoding device may change the method of calculating the encoding table according to the position of the target node 2 in the parent node.

(3) The three-dimensional data encoding device may refer to the encoding information of each node in the parent adjacent node when the reference to the parent adjacent node is not prohibited. For example, when reference to a parent adjacent node is not prohibited, reference to information (for example, occupation information) of a child node of a third node having a different parent node from the target node is permitted. For example, in the example illustrated in FIG. 65, the three-dimensional data encoding device acquires the occupancy information of the child node of the adjacent node X0 by referring to the occupancy code of the adjacent node X0 different from the target node and the parent node. The three-dimensional data encoding device switches the encoding table used for entropy encoding of the occupancy code of the target node based on the acquired occupation information of the child node of the adjacent node X0.

As described above, the three-dimensional data encoding device according to the present embodiment provides information on a target node included in an N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in three-dimensional data. (For example, an occupancy code). As shown in FIGS. 51 and 52, in the above-described encoding, the three-dimensional data encoding apparatus includes, among the plurality of adjacent nodes spatially adjacent to the target node, the first node having the same parent node as the target node. (For example, occupation information) is permitted, and reference to information (for example, occupation information) of a second node having a different parent node from the target node is prohibited. In other words, in the above-described encoding, the three-dimensional data encoding device allows reference to information of the parent node (for example, occupancy code), and information of another node (parent adjacent node) in the same layer as the parent node (for example, occupancy code). Reference) is prohibited.

According to this, the three-dimensional data encoding device performs encoding by referring to information of a first node having the same parent node as the target node among a plurality of adjacent nodes spatially adjacent to the target node. Efficiency can be improved. Further, the three-dimensional data encoding device can reduce the processing amount by not referring to the information of the second node having a different parent node from the target node among the plurality of adjacent nodes. Thus, the three-dimensional data encoding device can improve the encoding efficiency and reduce the processing amount.

For example, the three-dimensional data encoding device further determines whether to prohibit reference to the information of the second node, and in the encoding, prohibits reference to the information of the second node based on the result of the determination. Or allow. The three-dimensional data encoding apparatus further converts the bit stream that is the result of the above determination and includes prohibition switching information (for example, limit_refer_flag illustrated in FIG. 63) indicating whether to prohibit reference to the information of the second node. Generate.

According to this, the three-dimensional data encoding device can switch whether to prohibit reference to the information of the second node. Further, the three-dimensional data decoding device can appropriately perform the decoding process using the prohibition switching information.

For example, the information of the target node is information (for example, an occupancy code) indicating whether or not a three-dimensional point exists in each of the child nodes belonging to the target node, and the information of the first node is a three-dimensional Information indicating whether or not a point exists (occupation information of the first node), and the information of the second node indicates whether or not a three-dimensional point exists at the second node (occupation of the second node). Information).

For example, in the above-described encoding, the three-dimensional data encoding device selects an encoding table based on whether or not a three-dimensional point exists in the first node, and uses the selected encoding table to execute (For example, occupancy code) is entropy-encoded.

For example, in the above-described encoding, the three-dimensional data encoding device permits reference to information (for example, occupation information) of a child node of the first node among a plurality of adjacent nodes, as illustrated in FIGS. .

According to this, the three-dimensional data encoding device can refer to more detailed information of the adjacent node, so that the encoding efficiency can be improved.

For example, as shown in FIG. 53, in the above-described encoding, the three-dimensional data encoding device switches an adjacent node to be referred to among a plurality of adjacent nodes according to a spatial position in a parent node of the target node.

According to this, the three-dimensional data encoding device can refer to an appropriate adjacent node according to the spatial position in the parent node of the target node.

{For example, the three-dimensional data encoding device includes a processor and a memory, and the processor performs the above-described processing using the memory.

Further, the three-dimensional data decoding device according to the present embodiment provides information (for example, occupancy code) of a target node included in an N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data. ) Is decrypted. As shown in FIGS. 51 and 52, in the above-described decoding, the three-dimensional data decoding device obtains information on a first node having the same parent node as the target node among a plurality of adjacent nodes spatially adjacent to the target node. (For example, occupation information) is permitted, and reference to information (for example, occupation information) of a second node having a different parent node from the target node is prohibited. In other words, in the decoding, the three-dimensional data decoding device allows reference to information of the parent node (for example, occupancy code) and information of another node (parent adjacent node) in the same layer as the parent node (for example, occupancy code). Prohibit reference to.

According to this, the three-dimensional data decoding device refers to the information of the first node having the same parent node as the target node among a plurality of adjacent nodes spatially adjacent to the target node, thereby improving the coding efficiency. Can be improved. Further, the three-dimensional data decoding device can reduce the processing amount by not referring to the information of the second node having a different parent node from the target node among the plurality of adjacent nodes. As described above, the three-dimensional data decoding device can improve the encoding efficiency and reduce the processing amount.

For example, the three-dimensional data decoding apparatus further obtains, from the bit stream, prohibition switching information (for example, limit_refer_flag shown in FIG. 63) indicating whether to prohibit reference to the information of the second node. Based on the switching information, switching between prohibiting and permitting reference to the information of the second node is performed.

According to this, the three-dimensional data decoding device can appropriately perform the decoding process using the prohibition switching information.

For example, in the above-described decoding, the three-dimensional data decoding device selects an encoding table based on whether or not a three-dimensional point exists in the first node, and uses the selected encoding table to generate information on the target node. (For example, an occupancy code) is subjected to entropy decoding.

For example, in the above-described decoding, the three-dimensional data decoding device permits reference to information (for example, occupation information) of a child node of the first node among a plurality of adjacent nodes, as shown in FIGS.

According to this, the three-dimensional data decoding device can refer to more detailed information of the adjacent node, so that the coding efficiency can be improved.

For example, as shown in FIG. 53, in the decoding, the three-dimensional data decoding device switches an adjacent node to be referred to among a plurality of adjacent nodes according to a spatial position in a parent node of the target node.

According to this, the three-dimensional data decoding device can refer to an appropriate adjacent node according to the spatial position in the parent node of the target node.

{For example, the three-dimensional data decoding device includes a processor and a memory, and the processor performs the above-described processing using the memory.

(Embodiment 9)
The three-dimensional data encoding device can improve the encoding efficiency by using the adjacent node information of the target node when encoding the encoding information of the encoding target node (hereinafter, referred to as the target node). For example, the three-dimensional data encoding device switches an encoding table (probability table or the like) for entropy encoding an occupancy code of the target node using the adjacent node information. Here, the adjacent node information is, for example, whether or not a plurality of nodes (adjacent nodes) spatially adjacent to the target node are occupied nodes (occupied nodes) (whether or not the adjacent nodes include point groups ) And the like.

For example, the three-dimensional data encoding device may switch the encoding table using information indicating the number of occupied nodes (adjacent occupied nodes) among a plurality of adjacent nodes. For example, the number of occupied nodes among six adjacent nodes (left, right, upper, lower, front, and back) adjacent to the target node is calculated, and the occupancy code of the target node is entropy-coded according to the calculated number. May be switched over.

{Note that the three-dimensional data encoding device may use the pattern (hereinafter, “neighbour pattern”) instead of the number of adjacent occupied nodes. FIG. 68 is a diagram illustrating an example of an adjacent node and a process according to the present embodiment. For example, in the example shown in FIG. 68, adjacent nodes X0, Y0, and Z0 are occupied nodes, and adjacent nodes X1, Y1, and Z1 are non-occupied nodes that are not occupied nodes. In this case, the three-dimensional data encoding device calculates the value 21 of the adjacent occupation pattern by converting the bit string (Z1 Z0 Y1 Y0 X1 X0) = (010101) to a decimal number, and uses the 21st encoding table. To encode the occupancy code of the target node. Note that the three-dimensional data encoding device may use another value calculated using the value 21 as the value of the encoding table.

Here, a flag is used to calculate the adjacent occupancy pattern using the adjacent node information of the target node, switch the encoding table according to the value thereof, and switch whether to arithmetically encode the occupancy code of the target node. A NeighborPatternCodingFlag (adjacent pattern encoding flag) is provided. The three-dimensional data encoding device adds this NeighborPatternCodingFlag to the header of the bit stream or the like.

When NeighborPatternCodingFlag = 1, the three-dimensional data encoding device calculates an adjacent occupancy pattern using the adjacent node information of the target node, and switches the encoding table according to the value to arithmetically encode the occupancy code of the target node. I do. When NeighborPatternCodingFlag = 0, the three-dimensional data encoding device arithmetically encodes the occupancy code of the target node without using the adjacent node information of the target node.

{For example, when NeighborPatternCodingFlag = 1, the three-dimensional data encoding device calculates an adjacent occupation pattern using six nodes adjacent to the target node as shown in FIG. In this case, the value of the adjacent occupation pattern can take a value from 0 to 63. Therefore, the three-dimensional data encoding device switches the total of 64 encoding tables and arithmetically encodes the occupancy code of the target node.

For example, in the example illustrated in FIG. 68, the value of the adjacent occupation pattern is 21, and the three-dimensional data encoding device entropy-encodes the occupancy code of the target node using the 21st encoding table. Note that the three-dimensional data encoding device may use an index-th encoding table calculated from the value 21.

{Also, for example, when NeighborPatternCodingFlag = 0, the three-dimensional data encoding device determines the encoding table without using the value of the adjacent node information. For example, the three-dimensional data encoding apparatus sets the value of the adjacent occupation pattern to 0, determines the encoding table without using the value of the adjacent node information, and arithmetically encodes the occupancy code of the target node. That is, the three-dimensional data encoding apparatus sets the adjacent occupation pattern = 0 and uses the 0th encoding table. In other words, the three-dimensional data encoding device uses a predetermined encoding table.

As described above, the three-dimensional data encoding device calculates the adjacent occupation pattern according to the value of the NeighborPatternCodingFlag, and switches whether to perform encoding by switching the encoding table according to the calculated adjacent occupation pattern. This makes it possible to balance the coding efficiency with the reduction in processing amount.

Here, as a mode for encoding the target node, for example, a normal node (normal @ node) (or normal mode) in which the node is further divided into eight subnodes and encoded in an octant tree structure, There may be an early terminated node (or early coding mode) that stops coding in the structure and directly codes the position information of the three-dimensional points in the node.

{Circle around (3)} For example, when the number of point groups in the target node is equal to or less than a threshold value A, the three-dimensional data encoding device sets the target node as an early terminal node and stops octtree partitioning. Alternatively, when the number of point groups in the parent node (parent @ node) is equal to or less than a certain threshold B, the three-dimensional data encoding device sets the target node as an early terminal node and stops the octree splitting. Alternatively, when the number of point groups included in an adjacent node is equal to or smaller than a threshold value C, the three-dimensional data encoding device sets the target node as an early terminal node and stops octree partitioning.

As described above, the three-dimensional data encoding device determines whether the target node is an early terminal node using the number of point groups included in the target node, the parent node, or the adjacent node. It is also possible to stop the splitting of the tree and, if false, continue the splitting of the octant to perform encoding. Accordingly, the three-dimensional data encoding device can reduce the processing time by stopping the octree splitting when the number of point groups included in the target node, the parent node, or the adjacent node decreases. Note that the three-dimensional data encoding device may encode the three-dimensional position information of each of the point groups included in the node using the entropy encoding or the like for the early termination node.

FIG. 69 is a flowchart of a three-dimensional data encoding process according to the present embodiment. First, the three-dimensional data encoding device determines whether the target node satisfies the condition I to be an early terminal node (S4401). In other words, this determination is a determination as to whether or not the target node is likely to be encoded as an early termination node, that is, whether or not the early termination node can be used.

If the condition I is true (Yes in S4401), the three-dimensional data encoding device determines whether the target node satisfies the determination condition J of whether or not the target node is an early termination node (S4402). In other words, this determination is whether or not the target node is actually encoded as an early termination node, that is, whether or not the early termination node is used.

場合 If the condition J is true (Yes in S4402), the three-dimensional data encoding apparatus sets early_terminated_node_flag (early termination node flag) to 1 and encodes the early_terminated_node_flag (S4403). Next, the three-dimensional data encoding device directly encodes the position information of the three-dimensional point included in the target node (S4404). That is, the three-dimensional data encoding device applies the early termination node to the target node.

On the other hand, when the condition J is false (No in S4402), the three-dimensional data encoding device sets early_terminated_node_flag to 0, and encodes the early_terminated_node_flag (S4405). Next, the three-dimensional data encoding device sets the target node to a normal node, and continues encoding by octree division (S4406).

When the condition I is false (No in S4401), the three-dimensional data encoding device sets the target node to a normal node without encoding early_terminated_node_flag, and continues encoding by octtree division (S4406). ).

{For example, the condition J includes a condition that the number of three-dimensional points in the target node is equal to or less than a threshold value (for example, value 2). For example, the three-dimensional data encoding device determines that the target node is an early terminal node if the number of three-dimensional points in the target node is equal to or less than a threshold, and determines that the target node is not an early terminal node otherwise. .

{Circle around (1)} The condition I includes, for example, a condition that the hierarchy to which the target node belongs is equal to or higher than a predetermined hierarchy of the octree. For example, the condition I may include a condition that the target node is a layer larger than a node having a leaf (lowest layer) (whether the target node includes a space of a certain size or more).

{Circle around (1)} The condition I may include a node (sibling node) included in the parent node of the target node or a condition of occupation information of the sibling node of the parent node. That is, the three-dimensional data encoding device may determine whether or not the target node may be an early termination node based on occupation information of the sibling node or the sibling node of the parent node. For example, the three-dimensional data encoding device counts the number of occupied nodes among sibling nodes in the same parent node as the target node. Condition I includes a condition as to whether the counted value is equal to or less than a predetermined value. Alternatively, the three-dimensional data encoding device counts the number of occupied nodes among sibling nodes of the parent node of the target node. Condition I includes a condition as to whether the counted value is equal to or less than a predetermined value.

As described above, the three-dimensional data encoding apparatus terminates the target node early using the hierarchy of the target node in the octree structure, the occupation information of the sibling node of the target node, or the occupation information of the sibling node of the parent node. First determine whether there is a possibility of becoming a node. If there is a possibility, the three-dimensional data encoding apparatus encodes the early_terminated_node_flag, and otherwise, does not encode the early_terminated_node_flag. Accordingly, the three-dimensional data encoding device can perform encoding while appropriately selecting an early termination node while suppressing overhead.

{Circle around (3)} The three-dimensional data encoding device may provide an EarlyTerminatingCodingFlag which is a flag indicating whether or not to perform encoding using the early termination node (direct encoding mode), and may add the flag to a header or the like.

{Circle around (1)} Condition I may include a determination as to whether EarlyTerminatingCodingFlag = 1 is satisfied. By providing a mechanism for switching whether or not to use the early termination node (direct encoding mode) according to the value of EarlyTerminatingCodingFlag, it is possible to balance encoding efficiency with low processing amount.

{Circle around (3)} The three-dimensional data encoding device calculates the adjacent occupation pattern of the target node, and the condition I may include a condition of satisfying the adjacent occupation pattern = 0. As a result, when the adjacent node is in the non-occupied state, that is, when the three-dimensional points are sparse, the possibility that the early termination node is selected increases. Therefore, the three-dimensional data encoding device can improve the encoding efficiency by efficiently selecting the early termination node.

FIG. 70 is a flowchart of three-dimensional data encoding processing (early termination node determination processing) by the three-dimensional data encoding device according to the present embodiment. The three-dimensional data encoding device uses the NeighborPatternCodingFlag and the EarlyTerminatedCodingFlag.

First, the three-dimensional data encoding device determines whether the NeighborPatternCodingFlag is 1 (S4411). This NeighborPatternCodingFlag is generated in, for example, a three-dimensional data encoding device. For example, for example, the three-dimensional data encoding device determines the value of NeighbourPatternCodingFlag based on an encoding mode specified from the outside or an input three-dimensional point.

If 場合 NeighborPatternCodingFlag = 1 (Yes in S4411), the three-dimensional data encoding device calculates the adjacent occupation pattern of the target node (S4412). For example, the three-dimensional data encoding device uses the calculated adjacent occupation pattern for selecting an encoding table for arithmetically encoding an occupancy code.

On the other hand, if NeighborPatternCodingFlag = 0 (No in S4411), the three-dimensional data encoding apparatus sets the value of the adjacent occupation pattern to 0 without calculating the adjacent occupation pattern (S4413).

Note that the three-dimensional data encoding apparatus may initialize the adjacent occupation pattern with a value of 0, and may update the value of the adjacent occupation pattern if NeighbourPatternCodingFlag = 1.

Next, the three-dimensional data encoding device determines whether condition I is satisfied (S4414). For example, when EarlyTerminatingCodingFlag = 1, the three-dimensional data encoding device may determine whether the target node may be an early termination node using the value of the set adjacent occupation pattern. That is, the condition I may include a condition as to whether the set adjacent occupation pattern is 0.

{That is, the condition I may include a condition as to whether EarlyTerminatingCodingFlag = 1 is satisfied. The condition I may include a condition as to whether the adjacent occupation pattern = 0 is satisfied. For example, the condition I may be true if EarlyTerminatedCodingFlag = 1 and the adjacent occupation pattern = 0, and the condition I may be false otherwise.

Thus, when NeighborPatternCodingFlag = 1, the three-dimensional data encoding device can also use the adjacent occupation pattern calculated and set for encoding table switching in the early termination node determination (condition I). As a result, the amount of processing for recalculating the adjacent occupation pattern can be reduced. When NeighborPatternCodingFlag = 0, the three-dimensional data encoding apparatus can determine that at least one of the conditions I is satisfied by setting the adjacent occupation pattern = 0. Therefore, the three-dimensional data encoding device does not need to separately calculate the adjacent occupation pattern, so that the processing amount can be reduced.

{Circle around (1)} The condition I may include, for example, a condition that the hierarchy to which the target node belongs is equal to or higher than a predetermined hierarchy of the octree. For example, the condition I may include a condition that the target node is a layer larger than a node having a leaf (lowest layer) (whether the target node includes a space of a certain size or more).

{Circle around (1)} The condition I may include a node (sibling node) included in the parent node of the target node or a condition of occupation information of the sibling node of the parent node. That is, the three-dimensional data encoding device may determine whether or not the target node may be an early termination node based on the occupation information of the sibling node or the sibling node of the parent node. For example, the three-dimensional data encoding device counts the number of occupied nodes among sibling nodes in the same parent node as the target node. The condition I may include a condition whether the counted value is equal to or less than a predetermined value. Alternatively, the three-dimensional data encoding device counts the number of occupied nodes among sibling nodes of the parent node of the target node. The condition I may include a condition whether the counted value is equal to or less than a predetermined value.

{Circle around (1)} Condition I may include any of the above-described conditions, or may include a plurality of conditions. If a plurality of conditions are included as the condition I, for example, if all the conditions are satisfied, it is determined that the condition I is satisfied (true), and otherwise, the condition I is not satisfied (false). ) May be determined. Alternatively, it may be determined that the condition I is satisfied (true) when at least one of the plurality of conditions is satisfied.

Note that the processing in steps S4415 to S4419 is the same as the processing in steps S4402 to S4406 shown in FIG. 69, and redundant description will be omitted.

FIG. 71 is a flowchart of a modification of the three-dimensional data encoding process (early termination node determination process) by the three-dimensional data encoding device according to the present embodiment. The processing shown in FIG. 71 is different from the processing shown in FIG. 70 in that step S4411 is changed to step S4411A.

The three-dimensional data encoding device determines whether at least one of NeighborPatternCodingFlag = 1 and EarlyTerminatedCodingFlag = 1 is satisfied (S4411A). The NeighborPatternCodingFlag and the EarlyTerminatedCodingFlag are generated in, for example, a three-dimensional data encoding device. For example, the three-dimensional data encoding device determines the values of NeighborPatternCodingFlag and EarlyTerminatedCodingFlag based on an externally specified encoding mode or an input three-dimensional point.

If at least one of NeighborPatternCodingFlag = 1 and EarlyTerminatingCodingFlag = 1 is satisfied (Yes in S4411A), the three-dimensional data encoding device calculates the adjacent occupancy pattern of the target node and sets the value (S4412). When both NeighborPatternCodingFlag = 1 and EarlyTerminatedCodingFlag = 1 are not satisfied (No in S4411A), the three-dimensional data encoding device does not calculate the adjacent occupation pattern and sets the value of the adjacent occupation pattern to 0 (S4413).

Note that the three-dimensional data encoding device may initialize the adjacent occupation pattern with a value of 0, and update the value of the adjacent occupation pattern if NeighborPatternCodingFlag = 1 or EarlyTerminatedCodingFlag = 1. The subsequent processing is the same as in FIG.

{That is, when EarlyTerminatingCodingFlag = 1, the three-dimensional data encoding device determines whether the target node may become an early termination node using the value of the set adjacent occupation pattern. That is, the condition I may include a condition as to whether the set adjacent occupation pattern is 0.

Accordingly, when NeighborPatternCodingFlag = 1 or EarlyTerminatingCodingFlag = 1, the three-dimensional data encoding device calculates the adjacent occupation pattern of the target node, and the target node is the early termination node using the calculated value of the adjacent occupation pattern. Possibility can be determined. Therefore, the three-dimensional data encoding device can appropriately select an early termination node, thereby improving encoding efficiency.

Next, processing by the three-dimensional data decoding device according to the present embodiment will be described. FIG. 72 is a flowchart of a three-dimensional data decoding process (early termination node determination process) by the three-dimensional data decoding device according to the present embodiment.

First, the three-dimensional data decoding device decodes the NeighborPatternCodingFlag from the bitstream header (S4421). Next, the three-dimensional data decoding device decodes the EarlyTerminatingCodingFlag from the bitstream header (S4422).

Next, the three-dimensional data decoding device determines whether or not the decoded NeighborPatternCodingFlag is 1 (S4423).

If the NeighbourPatternCodingFlag is 1 (Yes in S4423), the three-dimensional data decoding device calculates the adjacent occupation pattern of the target node (S4424). Note that the three-dimensional data decoding device may use the calculated adjacent occupancy pattern to select an encoding table for arithmetically decoding the occupancy code.

When the NeighborPatternCodingFlag is 0 (No in S4423), the three-dimensional data decoding device sets the adjacent occupation pattern to 0 (S4425). Note that the three-dimensional data decoding apparatus may initialize the adjacent occupation pattern with a value of 0, and may update the value of the adjacent occupation pattern if NeighbourPatternCodingFlag = 1.

Next, the three-dimensional data decoding device determines whether the condition I is true (S4426). The details of this processing are the same as the processing in step S4414 in the three-dimensional data encoding device.

If the condition I is true (Yes in S4426), the three-dimensional data decoding device decodes the early_terminated_node_flag from the bit stream (S4427). Next, the three-dimensional data decoding device determines whether or not early_terminated_node_flag is 1 (S4428).

When early_terminated_node_flag is 1 (Yes in S4428), the three-dimensional data decoding device decodes the position information of the three-dimensional point in the target node (S4429). That is, the three-dimensional data decoding device applies the early termination node to the target node. When early_terminated_node_flag is 0 (No in S4428), the three-dimensional data decoding device sets the target node as a normal node, and continues decoding by octree division (S4430).

When the condition I is false (No in S4426), the three-dimensional data decoding apparatus does not decode the early_terminated_node_flag from the bit stream, sets the target node to the normal node, and continues decoding by octree division (S4430). ).

FIG. 73 is a flowchart of a modification of the three-dimensional data decoding process (early termination node determination process) by the three-dimensional data decoding device according to the present embodiment. The processing shown in FIG. 73 is different from the processing shown in FIG. 72 in that step S4423 is changed to step S4423A.

In step S4423A, the three-dimensional data decoding apparatus determines whether at least one of NeighborPatternCodingFlag = 1 and EarlyTerminatedCodingFlag = 1 is satisfied (S4423A).

When at least one of NeighborPatternCodingFlag = 1 and EarlyTerminatedCodingFlag = 1 is satisfied (Yes in S4423A), the three-dimensional data decoding device calculates the adjacent occupation pattern of the target node (S4424). When both NeighborPatternCodingFlag = 1 and EarlyTerminatedCodingFlag = 1 are not satisfied (No in S4423A), the three-dimensional data decoding apparatus does not calculate the adjacent occupation pattern and sets the value of the adjacent occupation pattern to 0 (S4425).

Note that the three-dimensional data decoding apparatus may initialize the adjacent occupation pattern with a value of 0 and update the value of the adjacent occupation pattern if NeighborPatternCodingFlag = 1 or EarlyTerminatedCodingFlag = 1. The subsequent processing is the same as in FIG.

Next, an example of the syntax of a bit stream generated by the three-dimensional data encoding device according to the present embodiment will be described. FIG. 74 is a diagram illustrating an example of the syntax of pc_header included in the bit stream. This pc_header () is, for example, header information of a plurality of input three-dimensional points. That is, the information included in pc_header () is commonly used for a plurality of three-dimensional points (nodes).

$ Pc_header includes NeighborPatternCodingFlag (adjacent pattern coding flag) and EarlyTerminatedCodingFlag (early termination coding flag).

NeighbourPatternCodingFlag is information indicating whether or not to switch a coding table for arithmetically coding an occupancy code using adjacent node information (adjacent occupation pattern). For example, NeighborPatternCodingFlag = 1 indicates that the encoding table is switched using the adjacent node information, and NeighbourPatternCodingFlag = 0 indicates that the encoding table is not switched using the adjacent node information.

EarlyTerminatedCodingFlag is information indicating whether to use an early termination node (direct encoding mode) (whether or not it can be used). For example, EarlyTerminatedCodingFlag = 1 indicates that an early termination node is used, and EarlyTerminatedCodingFlag = 0 indicates that an early termination node is not used.

FIG. 75 is a diagram illustrating a syntax example of node information (node (depth, index)). This node information is information of one node included in the octree, and is provided for each node. The node information includes occupancy_code (occupancy code), early_terminated_node_flag (early end node flag), and coordinate_of_3Dpoint (three-dimensional coordinates).

$ Occupancy_code is information indicating whether or not a child node of the node is in an occupied state. The three-dimensional data encoding device may arithmetically encode the occupancy_code by switching the encoding table according to the value of the NeighborPatternCodingFlag.

$ Early_terminated_node_flag is information indicating whether or not the node is an early termination node. For example, early_terminated_node_flag = 1 indicates that the node is an early termination node, and early_terminated_node_flag = 0 indicates that the node is not an early termination node. When the early_terminated_node_flag of the target node is not encoded in the bit stream, the three-dimensional data decoding device may estimate the value of the early_terminated_node_flag of the target node to be 0.

$ Coordinate_of_3Dpoint is position information of a point cloud included in a node when the node is an early termination node. If a node includes a plurality of point groups, coordinate_of_3Dpoint may include position information of each point group.

Note that the three-dimensional data encoding device may specify the NeighborPatternCodingFlag or the EarlyTerminatingFlag in the standard or the profile or level of the standard without adding the NeighborPatternCodingFlag or the EarlyTerminatedCodingFlag to the header. Accordingly, the three-dimensional data decoding device can correctly restore the bit stream by determining the value of NeighborPatternCodingFlag or EarlyTerminatedCodingFlag with reference to the standard information included in the bitstream.

The three-dimensional data encoding device may entropy encode at least one of the above-mentioned NeighborPatternCodingFlag, EarlyTerminatedCodingFlag, early_terminated_node_flag, and coordinate_of_3Dpoint. For example, a three-dimensional data encoding device binarizes each value and then arithmetically encodes the value.

Further, in the present embodiment, an octree structure is shown as an example, but the present invention is not limited thereto, and an N-tree structure (N is an integer of 2 or more) such as a quadtree or a 16-tree, or other The above method may be applied to the tree structure of.

Next, a configuration example of the three-dimensional data encoding device according to the present embodiment will be described. FIG. 76 is a block diagram of a three-dimensional data encoding device 4400 according to the present embodiment. The three-dimensional data encoding device 4400 includes an octree generating unit 4401, a geometric information calculating unit 4402, an encoding table selecting unit 4403, and an entropy encoding unit 4404.

The octree generating unit 4401 generates, for example, an octree from the input three-dimensional point (point cloud), and generates an occupancy code of each node of the octree. Note that, when EarlyTerminatedCodingFlag = 1, the octree tree generating unit 4401 determines whether or not the target node is an early terminal node by using the determinations of the conditions I and J. Alternatively, if false, encoding may be performed by continuing the octree splitting. Also, the octree generating unit 4401 may add a flag (early_terminated_node_flag) indicating whether each node is an early termination node to the bit stream. Accordingly, the three-dimensional data decoding device can correctly determine whether the node is an early termination node.

The geometric information calculation unit 4402 acquires information indicating whether or not an adjacent node of the target node is in an occupied state, and calculates an adjacent occupation pattern based on the acquired information. For example, the geometric information calculation unit 4402 calculates the adjacent occupation pattern by the method described with reference to FIG. Also, the geometric information calculation unit 4402 may calculate the adjacent occupation pattern from the occupancy code of the parent node to which the target node belongs. Alternatively, the geometric information calculation unit 4402 may store the encoded nodes in a list, and search for an adjacent node from the list. Note that the geometric information calculation unit 4402 may switch the adjacent node according to the position of the target node in the parent node. In addition, the geometric information calculation unit 4402 may switch whether to calculate the adjacent occupation pattern according to the values of the NeighborPatternCodingFlag and the EarlyTerminatedCodingFlag.

The encoding table selection unit 4403 selects an encoding table used for entropy encoding of the target node using the occupation information (adjacent occupation pattern) of the adjacent node calculated by the geometric information calculation unit 4402. For example, the coding table selection unit 4403 selects the coding table of the index number calculated from the value of the adjacent occupation pattern.

The entropy coding unit 4404 generates a bit stream by performing entropy coding on the occupancy code of the target node using the selected index-th coding table. The entropy coding unit 4404 may add information of the selected coding table to the bitstream.

Next, a configuration example of the three-dimensional data decoding device according to the present embodiment will be described. FIG. 77 is a block diagram of a three-dimensional data decoding device 4410 according to the present embodiment. The three-dimensional data decoding device 4410 includes an octree generating unit 4411, a geometric information calculating unit 4412, a coding table selecting unit 4413, and an entropy decoding unit 4414.

The # 8-ary tree generation unit 4411 generates an 8-ary tree of a certain space (node) using the header information of the bit stream and the like. For example, the octree generating unit 4411 generates a large space (root node) using the size of a certain space added to the header information in the x-axis, y-axis, and z-axis directions. Eight small spaces A (nodes A0 to A7) are generated by dividing into two in the y-axis and z-axis directions, respectively, to generate an octree. Nodes A0 to A7 are set in order as target nodes.

When the value of EarlyTerminatingCodingFlag obtained by decoding the header is 1, the octree tree generating unit 4411 determines whether or not the target node is an early termination node by using the determination of the condition I and the condition J. If it is true, the octree division may be stopped, and if it is false, the octree division may be continued and decoded. Also, the octree generating unit 4411 may decode a flag indicating whether each node is an early termination node.

The geometric information calculation unit 4412 acquires information indicating whether or not an adjacent node of the target node is in an occupied state, and calculates an adjacent occupation pattern based on the acquired information. For example, the geometric information calculation unit 4412 may calculate the adjacent occupation pattern by the method described with reference to FIG. Further, the geometric information calculation unit 4412 may calculate the occupancy information of the adjacent node from the occupancy code of the parent node to which the target node belongs. The geometric information calculation unit 4412 may store the decoded nodes in a list, and search for an adjacent node from the list. Note that the geometric information calculation unit 4412 may switch the adjacent node according to the position of the target node in the parent node. Further, the geometric information calculation unit 4412 may switch whether to calculate the adjacent occupation pattern according to the values of the NeighborPatternCodingFlag and the EarlyTerminatedCodingFlag obtained by decoding the header.

The encoding table selection unit 4413 selects an encoding table to be used for target node entropy decoding using the occupation information (adjacent occupation pattern) of the adjacent node calculated by the geometric information calculation unit 4412. For example, the three-dimensional data decoding device selects the index-th coding table calculated from the value of the adjacent occupation pattern.

The entropy decoding unit 4414 generates a three-dimensional point (point cloud) by performing entropy decoding on the occupancy code of the target node using the selected encoding table. The entropy decoding unit 4414 may decode and obtain information indicating the selected encoding table from the bit stream, and may use the encoding table indicated by the information to perform entropy decoding on the occupancy code of the target node.

{Each bit of the occupancy code (8 bits) included in the bit stream indicates whether or not each of the eight small spaces A (nodes A0 to A7) includes a point cloud. Further, the three-dimensional data decoding device divides the small space node A0 into eight small spaces B (nodes B0 to B7) to generate an octree, and each node of the small space B includes a point group. The occupancy code is calculated by decoding information indicating whether or not the occupancy code is used. As described above, the three-dimensional data decoding device decodes the occupancy code of each node while generating an octree from a large space to a small space. If the target node is an early termination node, the three-dimensional data decoding device may directly decode the three-dimensional information encoded in the bit stream and stop the octree splitting at that node.

Hereinafter, a modified example of the three-dimensional data encoding processing and the three-dimensional data decoding processing (early termination node determination processing) will be described.

The method of calculating the adjacent occupancy pattern of the target node is not limited to the method using the occupancy information of the six adjacent nodes shown in FIG. 68 and the like, and may be another method. For example, the three-dimensional data encoding device may calculate the adjacent occupation pattern with reference to an adjacent node (a sibling node of the target node) existing in the parent node of the target node. For example, the three-dimensional data encoding device may calculate an adjacent occupation pattern including the target node and position in the parent node and occupation information of three adjacent nodes in the parent node. When six adjacent nodes are used, information on an adjacent node whose parent node is different from the target node is used. When three adjacent nodes are used, information on an adjacent node whose parent node is different from the target node is not used. This allows the three-dimensional data encoding device to calculate the adjacent occupation pattern with reference to the occupancy code of the parent node, thereby reducing the processing amount.

In addition, the three-dimensional data encoding apparatus uses a method using the above-described six adjacent nodes (a method in which the target node and the parent node refer to different adjacent nodes) and a method using the three adjacent nodes (the target node and the parent node). (A method in which a node does not refer to a different adjacent node). For example, the three-dimensional data encoding device calculates the adjacent occupation pattern A using a method using six adjacent nodes for switching determination of an encoding table for arithmetically encoding an occupancy code. In addition, the three-dimensional data encoding device calculates the adjacent occupation pattern B using the method using three adjacent nodes for the possibility of the early termination node (condition I). Note that the three-dimensional data encoding device uses a method using three adjacent nodes for switching determination of the encoding table, and uses six adjacent nodes for determining the possibility of the early termination node (condition I). May be used. As described above, the three-dimensional data encoding device can control the balance between the encoding efficiency and the processing amount by appropriately switching the calculation method of the adjacent occupation pattern.

FIG. 78 is a flowchart of the three-dimensional data encoding process. First, the three-dimensional data encoding device determines whether the NeighborPatternCodingFlag is 1 (S4441).

If 場合 NeighborPatternCodingFlag = 1 (Yes in S4441), the three-dimensional data encoding device calculates the adjacent occupation pattern A of the target node (S4442). The three-dimensional data encoding device may use the calculated adjacent occupation pattern A for selecting an encoding table for arithmetically encoding the occupancy code.

On the other hand, when NeighborPatternCodingFlag = 0 (No in S4441), the three-dimensional data encoding apparatus does not calculate the adjacent occupation pattern A, but sets the value of the adjacent occupation pattern A to 0 (S4443).

Next, the three-dimensional data encoding device determines whether the EarlyTerminatingCodingFlag is 1 (S4444).

If EarlyTerminatingCodingFlag = 1 (Yes in S4444), the three-dimensional data encoding device calculates the adjacent occupation pattern B of the target node (S4445). The adjacent occupation pattern B is used, for example, for determining the condition I.

On the other hand, when EarlyTerminatingCodingFlag = 0 (No in S4444), the three-dimensional data encoding device sets the value of the adjacent occupation pattern B to 0 without calculating the adjacent occupation pattern B (S4446).

For example, the three-dimensional data encoding device uses different methods for calculating the adjacent occupation pattern A and the adjacent occupation pattern B. For example, the three-dimensional data encoding device calculates the adjacent occupation pattern A using a method using six adjacent nodes, and calculates the adjacent occupation pattern B using a method using three adjacent nodes. Similarly, in the three-dimensional data decoding device, a different calculation method may be used for the adjacent occupation pattern A and the adjacent occupation pattern B.

Note that the three-dimensional data encoding device may initialize the adjacent occupation pattern A with a value of 0, and may update the value of the adjacent occupation pattern A if NeighborPatternCodingFlag = 1. In addition, the three-dimensional data encoding device may initialize the adjacent occupation pattern B with a value of 0, and may update the value of the adjacent occupation pattern B if EarlyTerminatedCodingFlag = 1.

Next, the three-dimensional data encoding device determines whether or not the condition I is satisfied (S4447). The details of this processing are the same as, for example, S4414 shown in FIG. The difference is that the adjacent occupation pattern B is used as the adjacent occupation pattern in step S4414. That is, the condition I may include a condition that satisfies EarlyTerminatingCodingFlag = 1. The condition I may include a condition for determining whether the adjacent occupation pattern B = 0 is satisfied. For example, the condition I may be true when EarlyTerminatedCodingFlag = 1 and the adjacent occupation pattern B = 0, and the condition I may be false otherwise.

Note that the processing of steps S4448 to S4452 is the same as the processing of steps S4415 to S4419 shown in FIG. 70, and redundant description will be omitted.

FIG. 79 is a flowchart of a modification of the three-dimensional data encoding process (early termination node determination process) by the three-dimensional data encoding device according to the present embodiment. The processing shown in FIG. 79 is different from the processing shown in FIG. 78 in that steps S4453 and S4454 are added.

{Circle around (3)} If EarlyTerminatedCodingFlag = 1 (Yes in S4444), the three-dimensional data encoding device determines whether NeighbourPatternCodingFlag is 1 (S4453).

If NeighborPatternCodingFlag = 1 (Yes in S4453), the three-dimensional data encoding apparatus sets the value of the adjacent occupation pattern A to the value of the adjacent occupation pattern B (S4454).

When 場合 NeighborPatternCodingFlag = 0 (No in S4453), the three-dimensional data encoding device calculates the adjacent occupation pattern B (S4445).

As described above, when calculating the adjacent occupation pattern A, the three-dimensional data encoding apparatus uses the adjacent occupation pattern A as the adjacent occupation pattern B. That is, the adjacent occupation pattern A is used for the determination of the condition I. Thereby, when the adjacent occupation pattern A is calculated, the three-dimensional data encoding apparatus does not calculate the adjacent occupation pattern B, so that the processing amount can be reduced.

FIG. 80 is a flowchart of a modification of the three-dimensional data decoding process (early termination node determination process) by the three-dimensional data decoding device according to the present embodiment.

First, the three-dimensional data decoding device decodes the NeighborPatternCodingFlag from the header of the bit stream (S4461). Next, the three-dimensional data decoding device decodes the EarlyTerminatingCodingFlag from the bitstream header (S4462).

Next, the three-dimensional data decoding device determines whether or not the decoded NeighborPatternCodingFlag is 1 (S4463).

If the NeighbourPatternCodingFlag is 1 (Yes in S4463), the three-dimensional data decoding device calculates the adjacent occupation pattern A of the target node (S4464). Note that the three-dimensional data decoding device may use the calculated adjacent occupancy pattern to select an encoding table for arithmetically decoding the occupancy code.

If the NeighborPatternCodingFlag is 0 (No in S4463), the three-dimensional data decoding device sets the adjacent occupation pattern A to 0 (S4465).

Next, the three-dimensional data decoding device determines whether the EarlyTerminatingCodingFlag is 1 (S4466).

If EarlyTerminatingCodingFlag = 1 (Yes in S4466), the three-dimensional data decoding device calculates the adjacent occupation pattern B of the target node (S4467). The adjacent occupation pattern B is used, for example, for determining the condition I.

On the other hand, when EarlyTerminatingCodingFlag = 0 (No in S4466), the three-dimensional data decoding apparatus sets the value of the adjacent occupation pattern B to 0 without calculating the adjacent occupation pattern B (S4468).

{For example, the three-dimensional data decoding device uses different methods for calculating the adjacent occupation pattern A and the adjacent occupation pattern B. For example, the three-dimensional data decoding device calculates the adjacent occupation pattern A using a method using six adjacent nodes, and calculates the adjacent occupation pattern B using a method using three adjacent nodes.

Note that the three-dimensional data decoding apparatus may initialize the adjacent occupation pattern A with a value of 0 and update the value of the adjacent occupation pattern A if NeighbourPatternCodingFlag = 1. In addition, the three-dimensional data decoding apparatus may initialize the adjacent occupation pattern B with a value of 0, and may update the value of the adjacent occupation pattern B if EarlyTerminatedCodingFlag = 1.

Next, the three-dimensional data encoding device determines whether or not the condition I is satisfied (S4469). The details of this process are the same as, for example, S4426 shown in FIG. The difference is that the adjacent occupation pattern B is used as the adjacent occupation pattern in step S4426. That is, the condition I may include a condition that satisfies EarlyTerminatingCodingFlag = 1. The condition I may include a condition for determining whether the adjacent occupation pattern B = 0 is satisfied. For example, the condition I may be true when EarlyTerminatedCodingFlag = 1 and the adjacent occupation pattern B = 0, and the condition I may be false otherwise.

Note that the processing of steps S4470 to S4473 is the same as the processing of steps S4427 to S4430 shown in FIG. 72, and redundant description will be omitted.

FIG. 81 is a flowchart of a modification of the three-dimensional data decoding process (early termination node determination process) by the three-dimensional data decoding device according to the present embodiment. The processing shown in FIG. 81 is different from the processing shown in FIG. 80 in that steps S4474 and S4475 are added.

{Circle around (3)} If EarlyTerminatedCodingFlag = 1 (Yes in S4466), the three-dimensional data decoding apparatus determines whether NeighborPatternCodingFlag is 1 (S4474).

If NeighborPatternCodingFlag = 1 (Yes in S4474), the three-dimensional data decoding apparatus sets the value of the adjacent occupation pattern A to the value of the adjacent occupation pattern B (S4475).

If NeighborPatternCodingFlag = 0 (No in S4474), the three-dimensional data encoding device calculates the adjacent occupation pattern B (S4467).

As described above, when calculating the adjacent occupation pattern A, the three-dimensional data decoding apparatus uses the adjacent occupation pattern A as the adjacent occupation pattern B. That is, the adjacent occupation pattern A is used for the determination of the condition I. Accordingly, when calculating the adjacent occupation pattern A, the three-dimensional data decoding apparatus does not calculate the adjacent occupation pattern B, so that the processing amount can be reduced.

Note that the correspondence between the values of the various flags (0 or 1) and their meanings described above is merely an example, and the correspondence between the values of the various flags and their meanings may be reversed.

As described above, the three-dimensional data encoding device according to the present embodiment performs the processing shown in FIG.

The three-dimensional data encoding device determines whether the first flag (for example, NeighborPatternCodingFlag) indicates a first value (for example, 1) (S4481). When the first flag indicates the first value (Yes in S4481), the three-dimensional data encoding apparatus forms an N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data. A first occupation pattern (for example, adjacent occupation pattern A) indicating the occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the included target node is generated (S4482) (for example, S4442 in FIG. 79). And S4454).

Next, based on the first occupation pattern, the three-dimensional data encoding device does not divide the target node into a plurality of child nodes, and encodes a plurality of three-dimensional position information included in the target node. It is determined whether or not (for example, an early termination node) can be used (S4483) (for example, S4447 in FIG. 79).

When the first flag indicates a second value (for example, 0) different from the first value (for example, 0) (No in S4481), the three-dimensional data encoding apparatus does not include the first adjacent node different from the target node and the parent node. A second occupation pattern (for example, adjacent occupation pattern B) indicating the occupation state of the third adjacent node is generated (S4484) (for example, S4445 in FIG. 79). Next, the three-dimensional data encoding device determines whether the first encoding can be used based on the second occupation pattern (S4485) (for example, S4447 in FIG. 79).

{3} Also, the three-dimensional data encoding device generates a bit stream including the first flag (S4486).

According to this, the three-dimensional data encoding device can switch the occupation pattern of the adjacent node used to determine whether or not the first encoding can be used according to the first flag. This makes it possible to appropriately determine whether the first encoding can be used, thereby improving the encoding efficiency.

For example, when it is determined that the first encoding can be used, the three-dimensional data encoding device determines whether to use the first encoding based on a predetermined condition (for example, condition J) (for example, FIG. 79, S4448), if it is determined to use the first encoding, the target node is encoded using the first encoding (for example, S4450 in FIG. 79), and if it is determined that the first encoding is not used, The target node is encoded using the second encoding that divides the node into a plurality of child nodes (for example, S4452 in FIG. 79). The bit stream further includes a second flag (for example, early_terminated_node_flag) indicating whether to use the first encoding.

For example, the three-dimensional data encoding device determines whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, and determines whether the first occupation pattern or the second occupation pattern and the parent node It is determined whether the first encoding can be used based on the number of occupied nodes included. For example, when the number of occupied nodes included in the parent node is smaller than a predetermined number, the three-dimensional data encoding device determines that the first encoding is available, and determines whether the occupied state included in the parent node is available. If the number of nodes is larger than a predetermined number, it is determined that the first encoding cannot be used.

For example, the three-dimensional data encoding apparatus determines whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, and determines whether the first occupation pattern or the second occupation pattern is Based on the number of occupied nodes included in the grandfather node, it is determined whether the first encoding can be used. For example, when the number of occupied nodes included in the grandfather node is smaller than a predetermined number, the three-dimensional data encoding device determines that the first encoding is usable, and determines that the occupied state included in the grandfather node is included. If the number of nodes is larger than a predetermined number, it is determined that the first encoding cannot be used.

For example, the three-dimensional data encoding device determines whether or not the first encoding can be used based on the first occupation pattern or the second occupation pattern. It is determined whether the first encoding can be used based on the layer to which it belongs. For example, the three-dimensional data encoding device determines that the first encoding can be used when the layer to which the target node belongs is lower than a predetermined layer, and determines that the layer to which the target node belongs is higher than the predetermined layer. , It is determined that the first encoding cannot be used.

Further, the three-dimensional data decoding device according to the present embodiment performs the processing shown in FIG. First, the three-dimensional data decoding device obtains a first flag (for example, NeighborPatternCodingFlag) from the bit stream (S4491). The three-dimensional data decoding device determines whether the first flag indicates a first value (for example, 1) (S4492).

When the first flag indicates the first value (No in S4492), the three-dimensional data decoding apparatus includes the plurality of three-dimensional points included in the three-dimensional data in an N (N is an integer of 2 or more) binary tree structure. A first occupation pattern (for example, adjacent occupation pattern A) indicating the occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node to be executed is generated (S4493) (for example, S4464 and FIG. 81). S4475). Next, based on the first occupation pattern, the three-dimensional data decoding apparatus does not divide the target node into a plurality of child nodes and decodes a plurality of three-dimensional position information included in the target node (for example, early decoding). It is determined whether or not the end node can be used (S4494) (for example, S4469 in FIG. 81).

If the first flag indicates a second value (for example, 0) different from the first value (No in S4492), the three-dimensional data decoding apparatus determines that the target node and the parent node do not include the first adjacent node different from the target node. A second occupation pattern (for example, adjacent occupation pattern B) indicating the occupation state of the third adjacent node is generated (S4495) (for example, S4467 in FIG. 81). Next, the three-dimensional data decoding device determines whether the first decoding can be used based on the second occupation pattern (S4496) (for example, S4469 in FIG. 81).

For example, when it is determined that the first decoding can be used, the three-dimensional data decoding device acquires a second flag indicating whether to use the first decoding from the bit stream (for example, S4470 in FIG. 81), and If the second flag indicates that the first decoding is to be used, the target node is decoded using the first decoding (for example, S4472 in FIG. 81), and if the second flag indicates that the first decoding is not used, The target node is decoded using the second decoding that divides the target node into a plurality of child nodes (for example, S4473 in FIG. 81).

For example, the three-dimensional data decoding device determines whether the first decoding can be used based on the first occupation pattern or the second occupation pattern and includes the first occupation pattern or the second occupation pattern and the parent node. Based on the number of occupied nodes, it is determined whether the first decoding can be used. For example, when the number of occupied nodes included in the parent node is smaller than a predetermined number, the three-dimensional data decoding prosecution determines that the first encoding is available, and determines the occupied node included in the parent node. Is larger than a predetermined number, it is determined that the first encoding cannot be used.

For example, the three-dimensional data decoding apparatus determines whether the first decoding can be used based on the first occupation pattern or the second occupation pattern. Is determined based on the number of nodes in the occupied state included in (1). For example, when the number of occupied nodes included in the grandfather node is smaller than a predetermined number, the three-dimensional data decoding prosecution determines that the first encoding is usable, and determines the occupied node included in the grandfather node. Is larger than a predetermined number, it is determined that the first encoding cannot be used.

For example, the three-dimensional data decoding apparatus determines whether the first decoding can be used based on the first occupation pattern or the second occupation pattern, and determines the first occupation pattern or the second occupation pattern and the hierarchy to which the target node belongs. It is determined whether or not the first decryption can be used based on the above. For example, the three-dimensional data decoding device determines that the first encoding can be used when the layer to which the target node belongs is lower than a predetermined layer, and determines that the layer to which the target node belongs is higher than the predetermined layer. It is determined that the first encoding cannot be used.

Although the three-dimensional data encoding device and the three-dimensional data decoding device according to the embodiment of the present disclosure have been described above, the present disclosure is not limited to this embodiment.

Each processing unit included in the three-dimensional data encoding device, the three-dimensional data decoding device, and the like according to the above-described embodiment is typically realized as an LSI that is an integrated circuit. These may be individually integrated into one chip, or may be integrated into one chip so as to include some or all of them.

集積 Further, the integrated circuit is not limited to the LSI, and may be realized by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI, or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used.

In each of the above embodiments, each component may be configured by dedicated hardware, or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or a processor reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

The present disclosure may be realized as a three-dimensional data encoding method, a three-dimensional data decoding method, or the like executed by the three-dimensional data encoding device, the three-dimensional data decoding device, or the like.

The division of functional blocks in the block diagram is merely an example, and a plurality of functional blocks can be realized as one functional block, one functional block can be divided into a plurality of functional blocks, and some functions can be transferred to other functional blocks. You may. In addition, the functions of a plurality of functional blocks having similar functions may be processed by a single piece of hardware or software in parallel or time division.

The order in which the steps in the flowchart are executed is merely an example for specifically describing the present disclosure, and may be an order other than the above. Also, some of the above steps may be performed simultaneously (in parallel) with other steps.

As described above, the three-dimensional data encoding device, the three-dimensional data decoding device, and the like according to one or more aspects have been described based on the embodiments. However, the present disclosure is not limited to the embodiments. . Unless departing from the spirit of the present disclosure, various modifications conceivable to those skilled in the art may be applied to the present embodiment, and a configuration constructed by combining components in different embodiments may be in the range of one or more aspects. May be included within.

The present disclosure is applicable to a three-dimensional data encoding device and a three-dimensional data decoding device.

100, 400 Three-dimensional data encoding device 101, 201, 401, 501 Acquisition unit 102, 402 Encoding region determination unit 103 Division unit 104, 644 Encoding unit 111 Three-dimensional data 112, 211, 413, 414, 511, 634 Encoded three-dimensional data 200, 500 Three-dimensional data decoding device 202 Decoding start GOS determining unit 203 Decoding SPC determining unit 204, 625 Decoding unit 212, 512, 513 Decoded three-dimensional data 403 SWLD extraction unit 404 WLD encoding unit 405 SWLD code Conversion unit 411 input three-dimensional data 412 extracted three-dimensional data 502 header analysis unit 503 WLD decoding unit 504 SWLD decoding unit 620, 620A three-dimensional data creation device 621, 641 three-dimensional data creation unit 622 request range determination unit 623 search unit 624, 642 Receiver 626 Combiner 631, 651 Sensor information 632 First three-dimensional data 633 Request range information 635 Second three-dimensional data 636 Third three-dimensional data 640 Three-dimensional data transmitter 643 Extractor 645 Transmitter 652 Fifth three-dimensional data 654 sixth three-dimensional data 700 three-dimensional information processing device 701 three-dimensional map acquisition part 702 self-vehicle detection data acquisition part 703 abnormal case determination part 704 coping operation determination part 705 operation control part 711 three-dimensional map 712 self-vehicle detection three-dimensional data 810 3D data creation device 811 Data reception unit 812, 819 Communication unit 813 Reception control unit 814, 821 Format conversion unit 815 Sensor 816 3D data creation unit 817 3D data synthesis unit 818 3D data storage unit 820 Transmission control unit 822 Data transmission section 831, 832, 834, 835, 836, 837 Three-dimensional data 833 Sensor information 901 Server 902, 902A, 902B, 902C Client device 1011, 1111 Data receiving unit 1012, 1020, 1112, 1120 Communication unit 1013, 1113 Reception control unit 1014 , 1019, 1114, 1119 Format conversion unit 1015 Sensor 1016, 1116 3D data creation unit 1017 3D image processing unit 1018, 1118 3D data storage unit 1021, 1121 Transmission control unit 1022, 1122 Data transmission unit 1031, 1032, 1135 3D map 1033, 1037, 1132 Sensor information 1034, 1035, 1134 3D data 1117 3D data synthesis unit 1201 3D map compression / decoding processing Unit 1202 sensor information compression / decoding processing unit 1211 three-dimensional map decoding processing unit 1212 sensor information compression processing unit 1300 three-dimensional data encoding device 1301 division unit 1302 subtraction unit 1303 conversion unit 1304 quantization unit 1305, 1402 inverse quantization unit 1306 1403 Inverse transform unit 1307, 1404 Addition unit 1308, 1405 Reference volume memory 1309, 1406 Intra prediction unit 1310, 1407 Reference space memory 1311, 1408 Inter prediction unit 1312, 1409 Prediction control unit 1313 Entropy encoding unit 1400 3D data decoding Device 1401 Entropy decoding unit 2100 Three-dimensional data encoding device 2101, 2111 Binary tree generation unit 2102, 2112 Geometric information calculation unit 2103, 2113 Coding table selection Unit 2104 entropy coding unit 2110 3D data decoding device 2114 entropy decoding unit 4400 3D data coding device 4401, 4411 octree generation unit 4402, 4412 geometric information calculation unit 4403, 4413 coding table selection unit 4404 entropy coding Unit 4410 three-dimensional data decoding device 4414 entropy decoding unit

Claims

When the first flag indicates the first value,
The occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node included in N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data is described. Generating a first occupation pattern shown in FIG.
Based on the first occupation pattern, it is determined whether the first node can be used to encode a plurality of three-dimensional position information included in the target node without dividing the target node into a plurality of child nodes. And
When the first flag indicates a second value different from the first value,
Generating a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node;
Determining whether the first encoding can be used based on the second occupation pattern;
A three-dimensional data encoding method for generating a bit stream including the first flag.
If it is determined that the first encoding can be used,
Based on predetermined conditions, determine whether to use the first encoding,
If it is determined that the first encoding is used, the target node is encoded using the first encoding,
If it is determined that the first encoding is not used, the target node is encoded using a second encoding that divides the target node into a plurality of child nodes,
The three-dimensional data encoding method according to claim 1, wherein the bit stream further includes a second flag indicating whether to use the first encoding.
In the determination as to whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, the first occupation pattern or the second occupation pattern and an occupation state included in the parent node are determined. The three-dimensional data encoding method according to claim 1, wherein it is determined whether or not the first encoding can be used based on the number of nodes.
In the determination as to whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, the first encoding pattern or the second occupation pattern is included in the grandfather node of the target node. The three-dimensional data encoding method according to claim 1, wherein it is determined whether the first encoding is available based on the number of nodes in the occupied state.
In the determination as to whether the first encoding can be used based on the first occupation pattern or the second occupation pattern, the first occupation pattern or the second occupation pattern and the hierarchy to which the target node belongs are determined. The three-dimensional data encoding method according to claim 1, wherein it is determined whether or not the first encoding can be used.
Get the first flag from the bitstream,
When the first flag indicates a first value,
The occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node included in N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data is described. Generating a first occupation pattern shown in FIG.
Based on the first occupation pattern, determine whether or not it is possible to use first decoding for decoding a plurality of three-dimensional position information included in the target node without dividing the target node into a plurality of child nodes,
When the first flag indicates a second value different from the first value,
Generating a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node;
A three-dimensional data decoding method for determining whether or not the first decoding can be used, based on the second occupation pattern.
When it is determined that the first decoding can be used, a second flag indicating whether to use the first decoding is acquired from the bit stream,
Decoding the target node using the first decoding, when the second flag indicates that the first decoding is to be used;
The three-dimensional data decoding according to claim 6, wherein when the second flag indicates that the first decoding is not used, the target node is decoded using second decoding that divides the target node into a plurality of child nodes. Method.
In the determination as to whether the first decoding can be used based on the first occupation pattern or the second occupation pattern, the first occupation pattern or the second occupation pattern and the occupation state included in the parent node are determined. The three-dimensional data decoding method according to claim 6, wherein it is determined whether or not the first decoding can be used based on the number of nodes.
In the determination as to whether the first decoding can be used based on the first occupation pattern or the second occupation pattern, the first occupation pattern or the second occupation pattern is included in the grandfather node of the target node. The three-dimensional data decoding method according to claim 6, wherein it is determined whether the first decoding is available based on the number of nodes in the occupied state.
In the determination as to whether or not the first decoding can be used based on the first occupation pattern or the second occupation pattern, the determination is made based on the first occupation pattern or the second occupation pattern and a hierarchy to which the target node belongs. The method according to claim 6, wherein it is determined whether the first decoding can be used.
A three-dimensional data encoding device that encodes a plurality of three-dimensional points having attribute information,
A processor,
With memory,
The processor uses the memory,
When the first flag indicates the first value,
The occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node included in N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data is described. Generating a first occupation pattern shown in FIG.
Based on the first occupation pattern, it is determined whether the first node can be used to encode a plurality of three-dimensional position information included in the target node without dividing the target node into a plurality of child nodes. And
When the first flag indicates a second value different from the first value,
Generating a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node;
Determining whether the first encoding can be used based on the second occupation pattern;
A three-dimensional data encoding device that generates a bit stream including the first flag.
A three-dimensional data decoding device for decoding a plurality of three-dimensional points having attribute information,
A processor,
With memory,
The processor uses the memory,
When the first flag indicates a first value,
The occupation state of a plurality of second adjacent nodes including a first adjacent node having a different parent node from the target node included in N (N is an integer of 2 or more) binary tree structure of a plurality of three-dimensional points included in the three-dimensional data is described. Generating a first occupation pattern shown in FIG.
Based on the first occupation pattern, determine whether or not it is possible to use first decoding for decoding a plurality of three-dimensional position information included in the target node without dividing the target node into a plurality of child nodes,
When the first flag indicates a second value different from the first value,
Generating a second occupation pattern indicating an occupation state of a plurality of third adjacent nodes not including the first adjacent node having a different parent node from the target node;
A three-dimensional data decoding device that determines whether or not the first decoding can be used based on the second occupation pattern.